That has to do with the batterys ability to discharge. Nothing to do with the capacity. The reason why you'd get a better trigger response with a sub c because it's able to supply the motor with the needed current flow wich the 2/3 cannot supply fast enough. This is a different variable that deviates from the origional statement of capacity controls trigger response wich it does not, voltage does. What your describing is discharge rate, a POSIBLE bottle neck. It's like saying deans ultra plugs controls trigger response. Again, as stated above, it was said that capacity and not current draw was responsible for trigger response wich is wrong. But current draw is determined by...you guessed it voltage.

Bigger NIMH batteries just supply more tiny amounts of amperage to your starved motor, with a 7.4v LiPo you'll be able to supply all the amperage your motor would need, at a lower voltage, saving your trigger contacts. Just don't overdischarge the cells