Yes. That's the approximately constant-power region. It will be motor electrical power limited. Below that point, it's basically torque limited.
The little glitch is possibly a tweak that makes the take-off so smooth. My guess is that there is a lot of engineering in that little glitch, and increasing the power will require a lot of re-engineering to make the take-off as smooth as stock. There are all sorts of mechanical nasties (e.g. gear backlash, resonances) to be taken into account. Even just the fact that forward acceleration will cause your foot to come off the pedal a little (assuming it's not flat to the floor) can cause jerkiness.