The plan has become detailed enough to feel like progress.
There are lists, possible approaches, and a folder of examples. Each new piece of preparation suggests another thing to understand before beginning. The actual work remains conveniently untouched.
Eventually I make a rough version. It is smaller and less elegant than the one I imagined. It also answers a question that three days of planning had left unresolved.
Working gives an idea edges. We discover which parts resist us and which parts were only difficult from a distance. The next step becomes specific enough to take.
I keep the plan nearby, but turn it face down. For a while, the unfinished thing on the table can tell me what it needs.