Another one of the biggest benefits of a written PR/FAQ is that it enables the team to truly understand the specific constraints and problems that would prevent a new product idea from being viable and aligning on them.
You’re an inventor : Great PMs are usually creative types, who can generate and churn through many ideas all at once, to arrive at solutions to difficult and multi-faceted problems.
Features don’t work, in the sense that they can be easily gamed. Behaviour has an advantage over features in that you can describe any feature in terms of behaviour, but you can’t describe behaviour in terms of features.