I use to think that a engine dyno sheet would really help me to start with a shift RPM at or near peak HP RPM, NOT SO on every motor is what I found out
You can try shifting at peak HP RPM for several passes and then try short shifting it by 200 to 500 RPM below that, if it goes slower try 200 to 500 RPM above the peak HP RPM and it goes quicker and faster keep testing until you find out what your car really likes
The converter and several other things determine what shift points will work the best for each car
Most theory on drag racing are just that, theories