Q. When using a lightsaber, if four Stormtroopers combine fire at you, would lightsaber parry be used only once, or four times?
A. I’d say four times as you have to parry each damage

Q. How large of a shot can a lightsaber deflect? We all saw Luke deflect speeder-scale fire, and in Dark Empire, he deflected walker scale fire. I realize it would be extremely ridiculous to be able to deflect superlaser fire, but would it be possible to deflect starfighter lasers? How would the scale chart be used in this instance?
A. Sure, but the difficulty would be pretty great. Maybe the primary effect would be impact. The laser doesn’t burn the Jedi down on the spot, but his meditatin’ butt would certainly be thrown around.