Hi!
But there is a small difference in increasing V Speeds based on a Data card which is designed using STD ICAO Atmosphere Values and using speeds found in the runway tables for the specific airport at the current ambient AND assumed temperature.
According to all what i learned here and read its not to compensate a thrust loss, (which is compensated in the relevant Runway table) but to increase your kinetic energy upon lift off. A V1 and Vr nearer to V2 also helps to perform better in Engine Failure cases. But i know what you mean and it comes, in the end, to the same result.
We do increase from flex to TOGA thrust in case of Engine failure after V1 but it is not compulsory or required by performance requirements. Acceleration from V1 to V2 must be possible when you used speeds according the individual runway. BUT it must not be possible when using standard values like the ones found in a speed booklet.
Of course you cant play with it when youre runway field length limited but in all other cases it really makes sense.
Leo