Seriously, Vaders breathing didn’t get explained in movies till 20 years after there was 3 movies of him breathing. So what’s the big deal that Grevious coughs? Anyway, that was explained in the first clone wars cartoon. I checked out the dvd and saw it myself. Mace windu crushes his chest with the force.
I probably wouldn’t mind Grevious’ coughing, if Vader hadn’t had it before. Two villains with the same kind of breathing problems is simply unoriginal.
See, before I saw the movie (or maybe early into my viewing of it), I liked the cough. I thought Grevious was gonna be Maul on life support with robot legs. Kind of a beta-Vader that didn’t work as well yet. I would have kinda liked that. But, no.
This would have been a good payoff for the 3 films. Having Maul return, Obi Wan become obsessed with abandoning whatever his main mission was in order to track down ‘a ghost’ who killed his master, all while Palpatine uses this opening to end the war and turn an Anakin who has no Obi Wan to confide in would have given the story more importance. It would have increased Obi Wan’s guilt for the galaxy falling apart and his padawan becoming the 2nd most evil being in the galaxy.
Instead, because of Maul’s death in TPM, we are stuck with 2 subsequent fill-in villains that never seem very important.