To be clear, I'm not a moderator, nor have any authority on this site. I'm an ordinary user like everyone else, the most severe action I can take is posting a comment, down voting, or like I did - reach out via meta to address a serious quality issue.
I have no personal vendetta against Serpyre, I've no idea who he is or ultimately what the business he represents is. I have no objection to the quality of his English or the verbosity of his responses, and I have even offered positive comments and upvotes on some of his answers.
What I have an issue with is that the majority of his answers are completely off topic, wrong, argumentative or just wholly self promotional - he will make reference to Vanquish (his own company), 5X hosting (his own company) as being the only solution to any issue.
As Jonathan said, and it was his engagement with Serpyre (one of many Serpyre has had with users) that highlighted the lack of value this user offered. There is no place for arguments and personal debates on SE - and that's the exact reason why I felt Serpyre isn't welcome.
Despite being banned, he has continued to post the same low quality responses, that make no sense at all, do not contain a single fact or citable resource and either devalue Magento or suggest frankly dangerous advice. It is for this reason that he clearly isn't (with his current attitude) and appropriate fit here.
I don't have a direct issue with Serpyre, I have an issue with bad/dangerous advice - and regardless of who posts it, be it Serpyre or anyone else, I'll make efforts to remove it.
If I post a bad/wrong answer, I would hope others step in to correct me, so that future readers get good quality, safe advice.
As his answers and comments have been removed, you can form an opinion on him via his own site's content, http://serpyrecommerce.wordpress.com/2014/01/08/when-does-forum-moderation-restrict-business-growth-the-suspension/ and http://serpyrecommerce.wordpress.com/2014/01/08/when-does-forum-moderation-restrict-business-growth-real-world-example/ or his activity on Twitter, https://twitter.com/benmarks/status/499688346655154176
This site needs to grow, it needs people to feel welcome, and one less troll is going to achieve that.