I had a chance to test a plane for a harmonic vibration which occurred late in the take-off roll. The PF on these high tests was a TPS grad, TC and FAA DER, so well qualified, the test was run up to V1-10, close the throttles and let it roll. Every time, while an FTE took measurements, we neatly ran right up to the computed V1. Lesson: a plane has a a lot of energy approaching V1 and acceleration doesn't stop just because the power was closed.
GF
JT: retired last week, doing some outside business.