You know I played my share of rogues way back in the 2nd ed days. I had a blast with them, as I recall. I never got backstab damage versus undead, constructs, or a whole boatload of other enemies. Heck, I even failed to backstab the vast majority of plain vanilla humans and orcs that the party got into combat with. I never really felt short changed because I did less damage than the fighter, or because I had fewer hp than the cleric. I even failed to properly begrudge the wizard his ability to use spells.
I even failed to notice that we couldn’t do “tomb raiding”. In my defense I could have been thrown off by the fact that we actually did a fair bit of tomb raiding style adventures. I seem to recall finding traps that could have killed or seriously crippled our (the party’s) frontline fighter or, gods forbid, the cleric. Some of them I disarmed, a large number I simply found a way around. I picked locks to open doors because we were sure that there were terrible things in here with us, and the sound of the fighter bashing the door down would likely be heard by them as a dinner bell of sorts. The wizard could have popped the locks with a knock spell, but he didn’t have any memorized at the time. Since there was a thief in the party, he felt an acid arrow or the like would serve better in case (read: when) something went wrong. Besides, a single knock spell can only open two locks, and any door that is really hiding something would have at least three locks, right? He could have cast knock twice in that case, but 2 2nd level spells to open a door seems a touch... wasteful.
Now that I think about it, I didn’t even feel the obviously unfun nature of my plight when the big fight with the master of the tomb and his undead minions finally went down. As the fighter drew his blade and charged, the cleric held forth his holy symbol and made a turning attempt, and the mage began hurling all of the spells he didn’t waste trying to out thief/scout me, I was busy working my way over to the large statue/idol of the terrible demon/god that this unholy place was consecrated to. We had heard that the eyes were a large pair of flawless rubies, and as my gaze traveled the 12 or so feet up to this thing’s head, I saw that it was true. As my companions fought for their lives (and to keep the enemies off of me) I used my uncool and very, very unfun thief abilities to climb up, find and disarm some traps, and manage to pry the eyes loose. I used my lame tumble non-weapon proficiency to avoid damage as I jumped off of the now animated statue, and proceeded to yell “I’ve got them!!” and make tracks out of there.
Eventually some of the monsters caught up with us, though we had managed to stop the statue, namely by using some of those traps I had unfunly found, and uncooly routed us around rather than disarm. In my ignorance I managed to enjoy the combat I was forced into even though my short sword damage didn’t compete with that being handed out by the fighter and cleric of the party. I even found it kind of exciting… lame, I know.
That’s just one example of a “tomb raid”, not to mention of all the times I used a rogue to fast talk our way past a guard, pick-pocket some coin for an inn room or meal when the party was broke and starving, or plant some choice evidence on an NPC who thought that he was too clever to get caught.
In short I find arguments that thieves need to deal out the big damage in straight-up combats in order to be fun to be untrue on their face.