That's what I thought too. I used speckit quite a bit before and I've had mixed results at best. You are just moving ambiguity and code review from one place to another without really gaining anything.

I just rely on a log of user messages, all messages the user typed in a project as raw data and do a pass with agents to synthesize intent. Then use this for planning and validation of code. I think the user messages are the most valuable data in a project for this reason. Doing this reflection pass on messages takes just a few minutes even for thousands of messages. It keeps global perspective which is often lost in local work.