yea but they'd rev match in the process to stop the truck from shuddering
Rev match double clutching. Pretty much the same thing as rev matching except with a double clutch. Some truckies still do it.

some cars i drive so smoothly and some so jerky
umm different car, different clutch, different engine

also when u reverse, does it shuddeR? and why so? how can u make it not shudder and not ride the clutch
It shouldn't if you are doing it correctly. Its all about having the feel for the clutch.