I think the whole issue is Lucas trying to be tooo realistic. He sends the flash out first (light being faster than sound in the "real" world, but by the time the "sound" catches up, you are further along in the action and other stuff overrides it.
he does the same thing on the new explosions on the updated trilogy. this technique kinda started in Independance Day, but GL has really overdone it.
you end up with a sharp KaThang instead of an honest KaBOOM. it seems to be too much technology.