No. That lead to boxing. Putting required abilities on otherwise very non-interactive classes (warriors with defensive, clerics with CH, etc) meant you just boxed them and did other things. You may not remember Live during the vanilla > Luclin era, but having an out of group cleric that the warrior or wizard was running was pretty standard. Because they were required so instead of waiting for someone to want to play that incredibly boring class (up until that point) people just leveled them on another account so that their 15 a month wasn't spending several hours each week doing -nothing- because clerics were required to raid.
Bad game design. And the fact that you -could- bot a cleric effectively in a raid/group setting tells you exactly how badly designed that class/those encounters were. Any game that is box friendly to that point is clearly not a game requiring anything resembling "skill."
Further; during that time-frame it wasn't uncommon to have clerics/buffers/warriors pass around their info in the guild, because they were always sort of required to do shit and if someone wanted a night off, they would feel bad if they couldn't play a lot of times. And with the limited nature of server interactions (you could transfer characters after a time, but at first it was like... just level a new one) and the limited pool of people who wanted to play "needed" but boring classes, and you ended up with a tremendous amount of account sharing in the high end guilds. And if each class was as intricate as Nirgon seems to think, then it would be borderline impossible to play those classes you didn't normally to any level of ability required to actually do the "difficult" content in the game. Except, boxing boring classes for raid content was uh, you know, the thing to do. Dunno how prevalent it is on the EMU (I know they say they don't want you boxing but Verant also said not to use macroquest; nerds gonna nerd) but I know on the TLPs that stuff is typically also rampant.
If you can box a class at almost the same efficiency as someone playing it seriously, that's terrible class/game design.