While I completely agree that blankflag has been spamming the forum a lot lately, and yes I did find that annoying. I do completely disagree with the idea of muting him when he creates a decent topic for discussion. Sure if he would continue to spam, then feel free to mute him. But in this case this wasn't spam. You are essentially punishing him now because you don't like him. I just checked, and currently on the front page of the forums there are 2 threads started by blank, that's right 2 out of 29. I would hardly consider that 'spam'. Yes he may have been spamming earlier, but I would consider it more being active in the forum now, rather than spamming now. Everyone can change their ways, I'm not saying he necessarily has, but punishing him when there is nothing to punish for in my opinion is not a good way to moderate.
Too many a time playing online games over the years I have seen annoying people push the boundaries (like blankflag has done) then eventually get banned or muted, precisely as has been the case here, then go out on a rampage criticizing the site or company, or whatever or whoever runs a particular site or company for punishing them when they have done nothing wrong citing nothing but that one case. And new onlookers may see this and get a negative image of the site and not join having never found out the full story. It does happen.
In conclusion, I honestly don't care that much that you muted him, as he probably will have continued spamming in the future, however I really do disagree with the circumstance in which you muted him. Posting an interesting thread in my opinion does not deserve a mute, regardless how annoying you have been in the past. But any more spam, which is just spam for the sake of spam. Then feel free to mute.