Yes both cause bent forks. The only way to prevent them is with an aftermarket shifter that has positive stops(bolts to prevent the shifter from going too far).
Shifting hard enough to either put your knuckles into the dash or your elbow into the back seat can cause bent forks. The Tremec 3650 has built-in stops but they are plastic. Most people go with an aftermarket shifter to prevent this, as Red2000GT stated.