I get there’s a point at which you can’t generalize and have to slip into hyperbole, but come on. At 1st level every class except thieves, assassins, m-u, and illusionist in AD&D hits AC3 on a 17+/d20. Those four hit AC4 on a 17+/d20. The variety of ACs is wild. Most low hit dice monsters have an AC around 5. So claiming everyone always needs a 17 to-hit anything is beyond hyperbole.
I never said 'everyone always needs...' Nothing like that. I said there have been plenty of fights I can remember where nobody was hitting on anything less than a 17, it happens. Sure, lots of first level monsters have worse than AC4, many don't! Often you're fighting one or two tougher monsters, which often have better ACs, or they have something that situationally makes them harder to hit, or hard to damage, or whatever. The upshot being combat can quite easily drag on.
I played AD&D between once a week and once a month from 1984 through 2008. In that whole time we had maybe 3-4 combats last longer than an 60-90 minutes. And those were the epic finales of campaigns. At our fastest near the end of 4E our shortest combat was 2 1/2-3 hours. And it was a dill slog.
Look, nobody can obviously TELL you what you did, but it seems a tad exaggerated to me. I had MANY 4e fights that lasted 30 minutes, that was rather routine even. I have had many AD&D fights that lasted 2 hours, or even much longer now and then. If you want to tell me that TYPICALLY your AD&D fights were shorter, great. I am not going to argue that. When you tell me there was a consistent 500% difference in length, I am skeptical, quite skeptical.
Note what I've been saying about 'fights' in 4e too. They should be multi-dimensional affairs with more going on than hack-n-slash. So when the PCs bug out because they got what they wanted, that is quite common, and that means shorter fights. Same with monsters deciding to run off and not die, or the floor collapsed and everyone ended up hither and yon and the fight ended, etc.
The list of “substantial” monsters who have less than 3 attacks/round is long. It includes giants, golems, and liches amongst many others.
Many giants often have multiple attacks. Many golems have at least 2. Liches are almost surely casting spells, which is itself a lengthy process, lots lengthier in many cases than 4e powers, which at least resolve quickly. And a LOT of monsters get 3 or more attacks, really a lot.
The rules for breaking off from melee are on page 70 of the DMG.
D&D isn’t about doing what’s optimal, it’s about having fun exploring a fantasy milieu.
At this point I honestly need you to give me a specific, concrete example of what you think best practices are for running 4E because your experience and mine are so diametrically opposed that even if we are talking about the same game we don’t share a common frame of reference.
Yes, you can BREAK OFF from melee, you cannot move around, change (or even decide) who you are fighting, etc.
I think I did give you some examples. OK, I'm not sure exactly what counts as specific and concrete entirely. I recall a fight where the PCs were entering the top level of a tower, and it was filled with spider swarms. This was somewhere in the range of maybe 5th level, I don't recall exactly, but definitely mid-heroic. So the goal of the PCs was to get a book and break a curse. There was some terrain, I don't recall perfectly, but there was an area the spiders wouldn't go. It gave the PCs a chance to kind of play with some tactics, get themselves set up, and then go for the book. I think that fight was the end of an evening, and there were 2 other fights and at least one SC before that getting in, so about 4 encounters in 3 hours, plus some RP involved with figuring out where the tower was. Anyway, the spider encounter couldn't have been more than 45 minutes by itself, and it was a tough encounter. They got the book, and then one of the PCs had a hard time getting out of the room, it got a bit dicey.
I recall one that didn't go so well, it was earlier on. I had a mix of spiders, and the PCs were again in maybe high heroic, maybe just Paragon. There were a couple phase spiders, they jumped into the back ranks and bit the two casters, a wizard and a cleric. It was a save ends incapacitated condition, and man they just would not save. The other three PCs burned everything they had, every daily, everything, and it took FOREVER, but this is the point, there wasn't really a plot to this fight, it was just "get past the fliggin monsters" and it probably did take a good 90 minutes, and put a bit of a damper on that session, since 2 players got to do pretty much nothing for 90 minutes. That was about the last time I ever made a mistake like THAT! Although there was one similar time when a Barlgura just WOULD NOT DIE. lol.
Of course I also remember some 1e/2e encounters like that. too. I remember one where the PCs were maybe 4th level and a 12th level wizard had at them. The poor guy didn't want to burn up his own place, so he was tossing out weird effects. He webbed the party with a wand or something and then hit them with several spells. They managed to win eventually, sort of. Must have taken 3 hours to run that silly fight. I admit that it was kinda fun, at least for me