I think the philosophy of never banning anyone is a little misguided. It's adopted when people get upset about bannings occurring for what they take to be bad reasons. They overreact and decide that no one should ever be banned. But the banning itself wasn't what they really had an issue with. What they really had an issue with was the reason for the banning. So, the appropriate response is to get better reasons for banning. Here are a few examples of good reasons.
Posts like jt.
Is lame.
Reminds me of gpc/kstatefans.
Posts a lot on gpc/kstatefans.
Is on chum1 ban 'em list.
At this point, trying to PI yourself out of this mess is a losing battle. PI is for maintenance only. When you've got an infestation like this, you've got to get down and dirty. Just get rid of people you don't like regardless of when they joined.