WiFi-Nano aims to improve WiFi efficiency by reducing slot time from 9 microseconds to 800 nanoseconds. This addresses key overheads that reduce efficiency as data rates increase, like channel access, preamble, and acknowledgement overhead. WiFi-Nano employs speculative preamble transmission and ACKs, a lattice correlator for preamble detection, and probabilistic collision resolution to eliminate SIFS and reduce overhead by up to 100%, improving throughput. While it shows promise, the paper does not fully address impacts on DIFS or contention window size, or challenges of speculative transmissions.