Originally Posted by AngeloDS
It's necessary. Though if want it to be technically correct but also if you want to get more: spin, power, better angles and other various aspects it's a good idea to learn how to push off.
It's not needed as a lot of people cannot get the timing down. So staying on the ground works well for most. You can still have a serve in the 70s on the ground as long as you have a good wrist snap.
Great point, this is the part that can end up destroying peoples serves as it becomes too complex with many areas that can cause error.
I think you can get eve faster than 70mph
We see a trend in serves where people are bowing less and bending less as well as shortening the length/distance of the racket take back
This could be do to the rackets that are available, ect?