You learn more about a crew in the last 500 meters than in a whole season of practice. Pressure shows your people.

Practice is where people perform the version of themselves they have decided to be. The end of a race strips that off, because there is no attention left over for managing an image. What comes out then, the encouragement or the blame, the holding on or the quiet easing off, is closer to the real thing. That is information you cannot get any other way.

You do not need a race to see it. Watch the last hard set at practice, or the final hour of a long shift, and notice who steadies and who sharpens. Note it without announcing it, including what you did yourself.