Every user has the right to know why they are banned; that is fairly clearly spelled out in the COC. Unless there is clear evidence that something life-threatening or doxxing would occur as a result of delaying the final implementation of the ban (and there wasn't), moderation tends to err on the side of respecting users' rights to be informed of the reasons for and type of ban they face.
As for the "conclusive" proof you offered, it was hardly conclusive. As I said in previous public remarks, the evidence you offered was highly suggestive, but not sufficiently compelling to be actionable. At the time you presented the evidence to me, I concluded that if Sparrow was indeed a Type1 alt, both accounts would have to be permanently banned. I was not and am not prepared to take the step to permanently ban any user unless the evidence of their guilt is extraordinarily compelling. In this case, the evidence you provided was not. Though, both Virt and I continued to monitor the situation and to accumulate evidence in order to reach the evidentiary threshold necessary to take the step of perma-banning those accounts.
Perma-bans should not be undertaken lightly, in my view. That you have a personal grudge with Type1 is not something that I was going to allow to influence my reasoning. You may feel aggrieved by this process, which is certainly your prerogative, but that you are frustrated you didn't get your way or that things didn't play out exactly as you wanted them to is not going to change how I conduct moderation business. Feel free to protest, as is your right, but I hope this can be moderation's last word on the subject.