the part about getting the boss to sign off is purely a CYA maneuver. I think this person is in an awful situation and as soon as the boss says "why the heck did you do that?", the reply is "well, here's your signature".

Get a signature, but get it at the beginning of each iteration. Getting a CYA signature up front is worth nothing; if you have to pull it out towards the end of the project to wave at your boss, you're already fucked hosed.

In my experience, it's far better to keep a list of prioritized iteration features on the wall where everyone can see it all the time. Get your boss to sign that list at the beginning of each iteration.

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