The simple truth is that inline replying represents a massive cognitive load. Not just for the writer but for all the recipients. Not only does the email becom

The simple truth is that inline replying represents a massive cognitive load. Not just for the writer but for all the recipients. Not only does the email become very verbose with a lot of repeated paragraphs and psychedelic colors, it's also often content that you are already familiar with and don't really need to read again. Most email threads take place over a 24-48 hours period, which is enough for most people to have the context fresh in their mind, so top posting is a net gain for everyone. What is a very bad habit, though, is people not trimming long threads, especially when they forward such discussions.