The document discusses the case against using jumbo frames on the internet. It argues that while jumbo frames aim to improve transfer efficiency, path MTU discovery is flawed and unreliable, making it difficult to negotiate MTU sizes across network boundaries. The document also notes that jumbo frames are unnecessary today given modern networking capabilities, and that enabling them internet-wide would likely cause more problems than benefits due to the inherent issues with path MTU discovery and silently dropped packets from MTU mismatches.