This presentation begins with a simple exercise, follows with some simple math, and ends with another simple exercise. The intent of the exercises and the math is to illustrate the impacts of work in progress and multi-tasking. Limiting WIP is perhaps the single most impactful practice at our disposal to dramatically improve productivity. Originally presented at Agile New England on 5 May 2022.

1. WIP: A Couple Exercises and
Some Simple Math
David Hanson
dphanson63@yahoo.com
https://www.linkedin.com/in/david-hanson/
https://www.slideshare.net/DavidHanson5
May 2022

2. 2
This session will begin with a simple exercise,
follow with some simple math, and end with
another simple exercise. The intent of the
exercises and the math is to illustrate the impacts
of work in progress and multi-tasking.
Limiting WIP is perhaps the single most impactful
practice at our disposal to dramatically improve
productivity.
About the session… About me…
Limiting work in progress is a basic Lean concept,
which I have applied throughout my career,
beginning with college.
While my classmates lugged a backpack of books
to the library, I carried my one book, studying in-
depth one subject a night.
During my early career, I counseled my team to
have one primary task and one backup task.
Everyone’s WIP limit was two.
WIP
https://www.linkedin.com/in/david-hanson/
https://www.slideshare.net/DavidHanson5
David Hanson | ANE
2:22 AM

3. First, A Warm-up Exercise:
A Simple Dozen

4. A Simple Dozen:
Letters, Months, Roman Numerals

5. 5
Capital Letter Month Roman Numeral Rules of the Game: Getting Started
Get a couple pieces of paper (or front and back)
Draw two 3-column by 12-row grids with the
headers: Capital Letter, Month, Roman Numeral
Don’t fill in the grid yet
A Simple Dozen
David Hanson | ANE
2:22 AM

6. 6
Capital Letter Month Roman Numeral
A January I
B February II
C March III
D April IV
E May V
F June VI
G July VII
H August VIII
I September IX
J October X
K November XI
L December XII
Rules of the Game: Desired Outcome
Do not start yet
When done, results should look like this
A Simple Dozen
David Hanson | ANE

7. 7
Capital Letter Month Roman Numeral
A January I
L December XII
Rules of the Game
First time: Down
When I start the stopwatch, then begin
Write down all the capital letters, then all the
months, then all the Roman numerals, up to a
simple dozen
When finish, read time and enter time in chat
Count mistakes, if any, and enter count in chat
https://www.google.com/search?q=stopwatch
A Simple Dozen: Down
David Hanson | ANE

8. 8
Capital Letter Month Roman Numeral
A January I
L December XII
Rules of the Game
Second time: Across
When I start the stopwatch, then begin
Write down the 1st row, capital letter, month, Roman
numeral; continue with 2nd row to 12th row
When finish, read time and enter time in chat
Count mistakes, if any, and enter count in chat
https://www.google.com/search?q=stopwatch
A Simple Dozen: Across
David Hanson | ANE

9. 9
Capital Letter Month Roman Numeral
A January I
B February II
C March III
D April IV
E May V
F June VI
G July VII
H August VIII
I September IX
J October X
K November XI
L December XII
Results of the Game
First time: Down by Column
Who was faster down by column?
By 10% or 20%?
By 50% or 100%?
How many mistakes?
Second time: Across by Row
Who was faster across by row?
By 10% or 20%?
By 50% or 100%?
How many mistakes?
A Simple Dozen
David Hanson | ANE
2:22 AM

10. Work In Progress and
Multi-tasking

11. 11
Introduction
Limiting work in progress, thus reducing the need for multi-tasking, is the single most
impactful tool at our disposal to dramatically improve productivity
David Hanson | ANE
2:22 AM

12. 12
Maximizing Work In Progress
Focus Effort Month 1 Month 2 Month 3 Month 4 Month 5 Duration
Project α 1 month In progress In progress In progress Done 4 months
Project β 1 month In progress In progress In progress Done 4 months
Project γ 1 month In progress In progress In progress Done 4 months
Project δ 1 month In progress In progress In progress Done 4 months
Assuming no impact from multi-tasking
Average Activity Time (Effort): 1 month
Average Cycle Time: 4 months
Average Lead Time (Duration): 4 months
Average Process Efficiency (Activity Time ÷ Lead Time): 25%
David Hanson | ANE

13. 13
Maximizing Work In Progress
Focus Effort Month 1 Month 2 Month 3 Month 4 Month 5 Duration
Project α 1 month In progress In progress In progress In progress Done 5 months
Project β 1 month In progress In progress In progress In progress Done 5 months
Project γ 1 month In progress In progress In progress In progress Done 5 months
Project δ 1 month In progress In progress In progress In progress Done 5 months
Assuming a very modest impact from multi-tasking:
timelines extended by 25% or 1 month
Average Activity Time (Effort): 1 month
Average Cycle Time: 5 months
Average Lead Time (Duration): 5 months
Average Process Efficiency (Activity Time ÷ Lead Time): 20%
David Hanson | ANE

14. 14
Minimizing Work In Progress
Focus Effort Month 1 Month 2 Month 3 Month 4 Month 5 Lead Time
Project α 1 month Done 1 month
Project β 1 month Wait Done 2 months
Project γ 1 month Wait … Done 3 months
Project δ 1 month Wait … … Done 4 months
David Hanson | ANE
Average Activity Time (Effort): 1 month
Average Cycle Time: 1 month
Average Lead Time (Duration): 2.5 months
Average Process Efficiency (Activity Time ÷ Lead Time): 40%

15. 15
Minimizing WIP Impact
Average Cycle Time decreases from 5 months to 1 month
Average Lead Time decreases from 5 months to 2.5 months
Process Efficiency increases from 20% to 40%
Doubled the rate of productivity; same result in half the time
David Hanson | ANE
2:22 AM

16. 16
Concurrent
Projects
Overhead* Multi-
tasking**
Total
Available
Weekly per
Project
1 20% 0% 80% 32h
2 20% 20% 60% 12h
3 20% 40% 40% 5h 20m
4 20% 60% 20% 2h
5 20% 80% 0% 0h
Multi-tasking major inefficiencies:
context switching & meeting overhead
Context switching:
- Every interruption may cost 15
minutes to regain focus*
- 5 teams of 5 might lead to 20
interruptions/day (impact 5
hours/day or 25 hours/week)
Meeting overhead:
- Scrum Guide recommends ~5 hours
of events per week
- 5 teams would be 25 hours/week
*Popular UC Irvine study found impact was 23 minutes;
https://www.ics.uci.edu/~gmark/CHI2005.pdf
Impact of Multi-tasking on Individual Productivity
An arguably realistic outlook
*Standard project management assumption is 30% overhead (15% for time
off and 15% for distractions), so this is generous
**Gerald Weinberg, Quality Software Management: Systems Thinking,
stipulates 20% loss for each additional activity supported
David Hanson | ANE

17. 17
Concurrent
Projects
Overhead* Multi-
tasking**
Total
Available
Weekly per
Project
1 15% 0% 85% 34h
2 15% 15% 70% 14h
3 15% 30% 55% 7h 20m
4 15% 45% 40% 4h
5 15% 60% 25% 2h
Impact of Multi-tasking on Individual Productivity
A more optimistic outlook
Even a more modest assumption, still has a significant impact.
David Hanson | ANE

18. 18
Long hours
Heroic efforts with high-stress focus
Ignoring interruptions and requests for help
Working solo with own Kanban queue
Compensation Tactics Exceptions
Super-taskers
Popular university study found ~2.5% of people
are super-taskers, able to task switch with
minimal costs
https://pubmed.ncbi.nlm.nih.gov/20702865/
https://appliedcognition.psych.utah.edu/publications/supertasker_ii.pdf
https://www.bbc.com/future/article/20170210-a-test-can-identify-
supertaskers-but-only-a-few-pass-it
Multi-tasking Mitigation Tactics
How long can we sustain high-stress focus and long hours to compensate?
How many of us are in that pool of 1-out-of-40 supertaskers?
David Hanson | ANE
2:22 AM

19. 19
Takes 15 minutes to get into the Flow zone
Takes 23 minutes after an interruption
When in the zone, time disappears, productivity
soars
Modern work environments and smart phones
impede our ability to get in the zone
Techniques like Pomodoro can help with recurring
periods of intense focus followed by brief breaks
Anyone want to share an experience in the zone?
Getting in the Zone:
Csikszentmihalyi’s Flow Model
http://tomkenny.design/articles/flow-the-art-of-getting-in-the-zone/
https://en.wikipedia.org/wiki/Mihaly_Csikszentmihalyi
David Hanson | ANE

20. 20
Kanban Scrum XP
A sprint backlog based on yesterday’s
weather with a single sprint goal
Developing one story at a time all the
way to done with pair programming
Explicit practice to set WIP limits for
each phase of development lifecycle
How do popular Agile methodologies help reduce multi-
tasking and limit WIP?
David Hanson | ANE

21. 21
What are some Agile practices we can employ to reduce the
impacts of context switching?
Please share your suggestions…
David Hanson | ANE

22. 22
Conclusion
Minimizing work in progress can easily double process efficiency; halving lead times and doubling rate
of productivity
When considering overhead impact of multi-tasking and high stress mitigation strategies, actual impact
can be even greater
David Hanson | ANE
2:22 AM

23. Last, A Take-away Exercise:
The Name Game

24. The Name Game
My name is
D A V I D
https://www.crisp.se/gratis-material-och-guider/multitasking-name-game

25. 25
Need 1 Developer, 1 Product Owner, 1 Scrum
Master, and 3-5 Customers
Role Volunteers Role Overview
Developer will write names, so needs to type text
with Zoom annotation
Product Owner will coordinate with Customers
and confirm acceptance
Customers will think of two names (maybe your
mother’s and father’s name; not too short, not
too long)
Scrum Master will collect metrics
The Name Game
David Hanson | ANE
2:22 AM

26. 26
SM records start time
Developer asks each Customer for 1st letter, then
asks each Customer for 2nd letter, until names
complete (do not start next letter until every
customer served)
Each Customer takes turn telling Developer one
letter at a time from their name (no corrections)
PO checks the names with the Customer when all
names recorded
PO informs Developer of any corrections
SM records finish time when all names correct
First Pass
The Name Game
Rule: We Never Keep the Customer Waiting
First Pass: suggest using father’s name
David Hanson | ANE
P
M
S
Marstha
Sathish
Pierre

27. 27
We Never Keep the Customer Waiting
David Hanson | ANE

28. 28
Second Pass
SM records start time
PO sets the order for Customers
Developer asks one Customer for one letter at a
time, until have full name
Customer provides one letter at a time, correcting
any mistakes, as they arise, until done
Then next Customer goes, until all Customers
served
PO confirms Customers’ names correct
SM records finish time
The Name Game
Rule: Every Customer Deserves Our Full Attention
Second Pass: suggest using mother’s name
David Hanson | ANE
M-a-r-t-h-a
Martha
Satish
Pierre
S-a-t …

29. 29
Every Customer Deserves Our Full Attention
David Hanson | ANE

30. 30
How long did first pass take?
How many mistakes were made?
How long did second pass take?
How many mistakes were made?
Did one approach have clearly better results?
If so, why?
Capture Statistics Discuss Experiences
How did it feel as a customer, comparing first and
second passes?
How did it feel being the last customer, during the
second pass?
How did it feel as a developer, comparing first and
second passes?
How did it feel as a product owner, comparing
first and second passes?
The Name Game
David Hanson | ANE
2:22 AM

31. 31
Start Early, Finish Early?
Stop Starting, Start Finishing!
David Hanson | ANE

32. What was most useful for you?

33. David Hanson
https://www.linkedin.com/in/david-hanson/
https://www.slideshare.net/DavidHanson5
Session Feedback
https://www.surveymonkey.com/r/Z55MCHN