I believe a 3-stat design is superior than a two, or one-stat design. BUT: only if the content allows the player to determine the priority of those stats.
Lets say a fighter is Str, Con, Wis.
A Wis, Con, Str fighter would be like a warlord, good at buffing and debuffing, durable, but not a bruiser.
A Con, Wis, Str fighter would be more along the lines of a soaker, survivability, buffs and debuffs, but low damage.
A Str, Wis, Con fighter would be a more charismatic type, dishing out great damage but utilizing buffs and debuffs to make combat more interesting.
And of course you're got your typical Str, Con, Wis fighter who hits things, doesn't die, and says "What's a buff? Is that like, the size of my biceps?"
So basically, I approve of MAD, but only when MAD allows a player to be MORE creative, not less. Using multiple stats to generate even a typical character should lead to more interesting ways to conceptualize and play that character. It shouldn't lead to pigeon-holeing where players are forced to put their numbers into pre-defined stats in a pre-defined order otherwise risk being doomed to be a useless mook.