Also what do you mean use it for parkour? Like somebody could make a map where you have to destroy things during parkour?
Yes, possibly, but since most parkours are unbreakable, I was thinking the rocket jump feature would open up more parkour possibilities than just using jump boost. Although what you said is still a cool idea.
In 1.13 if you go to options -> controls -> mouse settings there is a new option called "raw input", that is not available in 1.12.2. This disables minecraft mouse acceleration and sets the input to raw mouse input. Can you make a mod that makes raw input option available in 1.12.2 and maybe lower? Thanks.