From a legal perspective, it is not a clarification but a change. The stupider course of action is to try to pretend it's a clarification instead of admitting it's a change. The Big XII chose to take the stupider route here.
But if I had to argue the Big XII's position in court, I would point to the comma and say the rule is legal gibberish as written, so some clarification is required. The Commissioner is authorized to clarify the rules. That's what he did.
It's just the intent of the rule was clear even if it was poorly drafted, and the "clarification" completely changed the intent of the rule.
Oh well.