Originally Posted by
Rajagra
If a cartridge razor pulls, all that happens is that skin is stretched. It remains flat against the cartridge because the cartridge is also flat and being held against the face. Eventually the stretching generates enough force for the hair to be cut and the stretched skin will snap back in place, whooshing over all those blades at once, leading either to a very close shave or irritation or both. That's my theory.
I guess to stop a straight from catching you really have to stretch the skin so the blade will cut hairs before it can stretch the skin any more. It follows that the sharper the blade, the less you need to stretch.