Power = torque x revs. You need power through the whole track so whatever you do to one side of the equation hurts the other side.
At low timing levels the motor has more torque. Torque, or turning force, is what you need to get weight on the move. That means that you can have higher gearing so you get speed on the straight, and it will pull the car out of the corner faster.
At high timing levels the motor will get to a higher rpm at the expense of the torque. In these situations the gearing is lower so that the car will pull out of the corners and then use its higher revs to get speed on the straight.
In both cases, give or take, you are putting the same energy in, so you will get the same power out. It just comes out in different ways. The 'give-or-take' bit is that there is a 'sweet spot' in there where the motor is at its most efficient so giving you the best lapt time for the lowest energy used. Less energy used means higher cell voltage through the run and therefore better performance towards the end of the race. But...
A dc electric motor retards under load. The interaction of the permanent magnet (rotor) and electromagnet (coils, or stator) fields is such that as the load on the motor increases, the effect is to reduce the timing. So, if you want more total power, then you have to start throwing some dynamic timing at it - boost.
When the static timing is low, the motor is suited to low revs and producing good torque. AS the revs rise the motor retards and so it tops out at a lower rpm. When the static timing is high, the motor is over-advanced at low revs so can't spin up so easily, but then tops out at a higher rpm.
Dynamic timing is in effect adding timing in as the revs rise to cancel out the effect of the retarding caused by the interaction of the magnetic fields. That's why these speedos are so devastatingly effective, because they work to cancel out the natural restraints on a motor enforced by the Laws of Physics.
Having said all that, if you gear wrongly you will toast the motor whatever the timing, boost or turbo you use. If you want more straightline speed then the best answer is to put in a faster motor, or dial in some boost. If you go the boosted route there is no need to add static timing or change gearing, just bring the boost in late in the rev range so you get more revs without upsetting the torque low down. Make sure static timing is at zero and then work with the boost settings. HTH
