Hmm, I personally would say that this is impossible. The first batch of mead that I had turned out around 18% alcohol content. Anything is possible. It takes a very robust yeast to get even close to that. 17 days sounds more like a distilling process. I am not sure what percentage of alcholol is 50 proof. The yeast must have been a very high tolorant yeast, most I have seen was at 25% al content. And that is pushing it, which would requre sweetening it when it slows down and filtering it out. My first batch I started Last Laborday and bottled it ready to drink mid January. Ofcourse I used unfiltered honey. Using store bought honey might change the time as it is very filtered. It took 4 rakings to get it a wonderful clear honey color and it was desert sweet. You would probably call it sickening sweet. I suppose you could rack it every day until it is past the primary (about 1 1/2 to 2 weeks) and then filter and distill the remainer. Might be more of a rum than a mead.

My Mead ending up pretty potent, You can get buzzed on just one 12 oz bottle if you don't sip it and drink it like soda. A nice mellow buzz if you drink it 30 min can result.

Thanks for letting me know. It is odd to hear this type of story. I wonder if he is using an evaprative technique.