It's not always best practice to train a full T2B if you cannot connect the reps. Doing more reps under lighter load will help you learn to establish rhythm (of the torso swing) and ROM (of the legs) that will serve as the foundation of your kipping T2B to come!
If your plan is to do a T2B that is less than the full thing, you are eliminating some of the ROM from the leg swing. ROM takes time, so by lessening the ROM you are in fact lessening the amount of time it takes for your legs to swing from behind you to the bar (and back down).
Body proportions do affect the tempo of a swing (short torso and arms means faster swing tempo, and the inverse is true as well), but as a general guideline for Half T2B + you should be aware of where you are jumping and how it should match your ROM as a shorter ROM should also have a faster tempo (swing of the torso).
Check out this magnificent drawing (I'm kidding). If you know what your goal "Highest Point" of your leg swing is going to be, adjust your starting position accordingly!
This is added in the First 4 T2B program on Week 6, Day 3.