> The developers build in lots of "fat" to their estimates [...] Then they're cheating, i.e., not being honest. Agile requires discipline and transparency. If

> The developers build in lots of "fat" to their estimates [...] Then they're cheating, i.e., not being honest. Agile requires discipline and transparency. If you avoid those overheads (and they are an overhead) then why bother? There's a difference between "business" and "productiveness". If a dev finishes a "1 hour task" in five minutes then they should move on to their next task. When you look at the burn down/up charts the discrepancy will be visible. Part of the point of agile is precisely to expose poor estimation.