Hey Outdoorsguy,
I think you have a skewed perspective of what happened. From what I saw, the guy let out a yell as the leopard's claws dug in and as he bit his arm. From what I could see, being a former medic, the guy's arm was broken. And those puncture marks weren't anything to laugh at. Fortunately, one of the assisting guides shot the cat and put him down -- my understanding from an earlier contributor is the cat HAD been shot, but it wasn't enough to stop him prior to that.
It's said that for every second a leopard is ON you, you'll need 100 stitches. It appeared this cat had maybe a second, perhaps less on the guy, before it was killed. And yet look at all the holes in him! I would be very hesitant to judge like this being you weren't there. Maybe you were attacked by a Grizz, but I doubt you were torn into by it. While screaming doesn't help -- and may be counter productive -- it would take a hell of a lot to remain silent under such excrutiating pain as a wild animal like that taking a chunk out of you.
I hope NEVER to be put to the test myself.