Both Stratholme and Scholomance could be run with up to 15 players in a raid. When they dropped it to a 5-man limit, I remember all of the screeching and crying because "now no one will ever run it!" Of course, my friends and I wound up running them way more often after it was dropped to a 5-man. Not only were we finally able to complete the quests, the zones turned out to be very manageable once you "unlearned" all of the bad habits you picked up while 15-manning it. UBRS went from 15 to 10, same thing-- people complaining that they'd never run it, and people running it all the time with no issues.

That may have been the last time that Blizzard actually made something in the game harder.