Straight out burninating a tag can leave things kind of hanging and hard to search on. group is definitely useful, the problem is its ambiguity due to multiple platforms using it - the same thing occurred for the like tag.
Potentially a better course of action is to disambiguate it - this means editing the questions to change the tag, for example group on a database or SQL related question becomes group-by, when used on a facebook related question it becomes facebook-group the same for LINQ, etc..
Once it has been eliminated then it could be blacklisted (although maybe that could be done straight away, it would mean that any question with that tag that gets edited would also have to have the tag changed before submitting the edit?).
So.... the suggested retags should be:
(additions & suggestions welcome).
Currently there are 1304 questions still tagged with group.