Oh, so you're blind now.
There is a clear visual speed up if you time the body straight correctly after the feint, it's been confirmed already. Watch the #1 Player on Ranked on PS4, EdParker02, he does it ALL the time.
https://youtu.be/5xqaUEMzqOI 11:30-11:33 you will clearly see the sped up body cross.
You can speed up the lead body uppercut too with the jab feint.
Nobody said anything about a damage increase, it's the speed boost people have an issue with.
Do you actually play Ranked at all? Genuine question.