Do you take notes during a live coding round or does that look like stalling?

I think better when I write the constraints down. But on a shared screen there's this pressure where every second you're not typing actual code feels like dead air you're being charged for.

Last round I opened a scratch file and wrote out the inputs, the edge cases and a rough plan as comments before touching anything. The interviewer was completely quiet through it and I couldn't tell if that read as methodical or as visibly panicking.

What's the actual norm here?