I'm with you. The first phase is really fast-paced uber-productive (as you assemble all the bits from past experiences), and the second phase really slows down

I'm with you. The first phase is really fast-paced uber-productive (as you assemble all the bits from past experiences), and the second phase really slows down as you deal with the nitty gritty of implementation and attention to detail. Just doing the first phase is the equivalent of being an ideas guy. I.e. useless without the implementation.