Thought about this last night, I was flying out and the Capt back. I fly a 738. So we get to 80kts, he calls, our SOP's require I look inside call 'Cross Checked' then back to the action, still below 90kts, even with a light load. If there is no response pnf has time to call 100kts, and still has time to reject quite safely. no drama, same on the return leg, fully loaded, no problems stopping if needed.
As to using up 75% of the runway, sorry not sure where that comes from, we don't.