Even if it was his, having a reserve that high for a jersey for a player that has not won a national championship, a Heisman, etc, is just way too much without provenance. Maybe if they could validate that it was worn for a significant game or actually worn by Boyd. All in all $400 is just too much for something that has so many red flags. I acquired a centennial full uniform, a Raymond Priester centennial patch home jersey, and a centennial helmet for about the same amount of money, and they were auctions as well with authentication. The Raymond jersey is worth more than Tajh's jersey (no offense he is an awesome athlete and one of my favorites) because he set and still holds the Rushing yards record for a single game, season, and career for Clemson and wore that jersey the whole season he set those records. The only Boyd jersey that would probably bring more would be the one he wore for the ACC championship and possibly the last Chick-fil-a Bowl when they won over LSU (maybe). The main problem with that jersey is that there is no documentation, the size does not match (as shown above) and the seller could not give any information on its provenance. With all of that then you might get $400 just because he is a hot current player right now and people get caught up in it all and are blinded by that fact. For the buyers sake I hope he ends up somehow being able to prove that Boyd wore that size and wore that jersey to justify what they spent.
EDIT: Fixed some spelling errors.