I don't think the presence of a filter should be seen as an altogether bad thing.
I've helped moderate a few forums, and when 99% of your spam has the word 'Viagra' or 'Cialis' in it, and one message in a thousand, from one of your legitimate posters has a "naughty" word like that in it, it gets filtered. Not necessarily killed, but filtered. Rather than having to hit [delete] on thousands of posts, you simply scan the filter folder and make sure the few posts from known posters that do get filtered are then moved back into the general forum.
Now, if BigMike had such a filter..and I can't blame him for having one...as many threads that have 'TG' in them will likely require some monitoring and moderating!!...and someone good gets caught in the filter, and BigMike just didn't notice it...can't we all see that it was an innocuous error?!
But conspiracy theories are more fun!!
