Heard from a pilot who used to do tests, including RTO test after maintenance on A330/340's. The discussion was about whether to use reverse during RTO, where he simply said: first time he did it his hands got thrown off the throttles by the violent braking action. By the time he had overcome the sensation and found his way back to te reverse thrust, he was pretty close to a standstill.
There is a reason why a not properly working shoulder harness is a no-go...