And on the other side of the coin, my DS can take 4 hours to do one hour's worth of work, complaining about how unfair school is, and life in general, moaning, groaning, stalling, getting sidetracked, finding a pencil, finding a piece of paper, finding (or not finding because it's still at school) the book, and so on, ad infinitum.

If he'd actually just sit down and do it, it would take him 15 minutes.