OB1 and GQJ were in a FIGHT!!! If you don't do anything else but defend you are going to get killed, you don't want that now do you??
Luke DID stroke first, but wasn't Vader the first one to ignite his sabre? Any way, it is not about that, defence means: don't storm up to a guy and cut him open, first try to talk; but against a Sith that is difficult.
Luke also stroke at the emperor, but watch the movie and you'll see that the emperor is trying to get Luke to the Dark Side, and Lukes gets angry with him and strikes.
I agree with king jedi
about why not using the force rush I agree with king jedi and tomacco dude do something for a change
ob1 devoted his life to serve the force and the republic so did qui-gon jinn. ob1 honoured qui-gon jinn and did all he could to help him
(btw your idea makes no sence
why would ob1 scream like hell when qui-gon was killed there was no-one there to fake for just him and dm and the other thing is he wouldn't got all pumped up to killin' dm if he didn't give a damn about qui-gon)