We can argue back and forth about 'dungeon etiquette' all we want but, at the end of the day, some people like to go fast, others like to go slow. No one's going to convince the other side that their way is better, because it's all a manner of personal taste. I've yet to see this be a major issue in game as I haven't witnessed a single 'confrontation' between players wanting to either go faster or slower. This leads me to believe I'm either the luckiest player ever or the people making a mountain out of a molehill are the ones instigating problems in their respective groups.

If you want to go fast, then go fast and hopefully the rest of the group follows suit. Same for people wanting to go slow. If you can't handle the pace, drop group, take the penalty and go take a breather. Arguing won't make things go faster/slower, it'll only make the rest of the group quietly resent you for making things awkward.