There is no argument in my mind that the book figures are valid and correct.
While I respect the book V1 and I know that fudge factors and decision times have been built into those V speeds, the experience of observing many botched aborts in simulator prof checks and when training for type ratings has convinced me there is a theoretical world and a real world when it comes to lightning fast decision making with an event close to V1. And we all know you have to be real quick and perfect on a balanced field length abort. Few pilots are both.
Certainly V1 must be correctly bugged using the book figure. And V1 is called when it arrives but once I pass beyond 15 knots below V1 and heading fast towards the bugged V1, I can afford to relax a little as I know the danger of a botched abort is less because I ain't stopping for no man - unless it is a catastrophic event where continuing is not on. Of course commonsense prevails when it comes to Vmcg. Its called playing the statistics, I suppose.