Players having multiple characters is a different matter entirely from players having henchmen and followers. I do allow both, but I'll only permit a player to run one player character at a time during a given adventure. So if, for example, Bob the player happens to have a 5th level fighter, a 4th level magic-user, and a 2nd/3rd magic-user/thief in his stable of player characters, only one of them ever gets to be run during a given game session. (And the stipulations given in AD&D against players with multiple characters sharing magical items between then are strictly observed: that way, Bob can't just heap three characters' worth of magical items on whichever one character is going on the adventure that week.)