I think most of us had the advantage of growing up in the pre-Internet era, where the expression "Ready, Fire, Aim" was a joke and not a description. From this perspective the simple recommendation is "Let him back on, but he has to realize he's on 'double, secret probation' (aka 'best behavior')." That's my official view.
But here's my unofficial gut reaction: (a) I think 'Fishslayer' is a young, impulsive person -- under age 30 in any event; (b) most young people don't really change even if you give them second and third chances -- any more than old fellows do; (c) but if Fishslayer actually sees some value in his being allowed to participate on the Board then he'll be big enough to apologize under his own name and (d) he knows that as a condition of being let back on that "third strike you're out", and realizes that the Board is about constructive advice then reinstate him. Otherwise, forget it: stay angry and write about it, but do so on another bulletin board and leave Bob's place alone.
* * * * *
If he wants to vent off-line about anything and everything -- starting with this post -- then shoot me an email and I can turn it around overnight. (I'm at bawest@pacific.net.sg.)