if you have "just enough" lighting for your plants, I wouldn't mess with them. If you have more than plenty of lumens shining down on your grow space, I would do some LST/Topping
if you're growing in anything less than a 1gallon container(soil), I wouldn't mess with them, but that's just my humble opinion. I leave myself open to be corrected
I don't think that LST/Topping ALWAYS equals larger yield, but most likely it will. However, whether it's the type of bud-size/bag appeal quality your looking for, LST/Topping might detriment that unless you have the root-mass/enough lighting to support bigger fatter buds. space availablity is important too
