There is already a user with that name. He hasn't been online since the day he registered in 2007, but that doesn't matter.
If he hasn't been online here since the day he registered 6 years ago, then how can it not matter?
It's quite obvious that whoever he is, he is not a member of this forum - his non-participation - ever - proves that.
If a username has not been used at all for a few years, it is only common sense that that username be removed from the username list, thus freeing it up for others to use. It makes no sense at all to keep it as an active username when it clearly is not.
Also, I did a search of members names a couple of weeks ago, and the username Deuce did not even show up.