Not very convincing. Whose to say that the 'baggy t' didn't come from a fat and tall clothing store with a new label slapped on it. Now, if we were talking about, perhaps, a trophy or a medallion that Nasser won for an event then we'd be cooking with gasoline. Something with a unique personal angle that can be readily identified without explantion. I collect books (i know, I know 
and getting them signed by the author is key to their value, both economically and to me in my little collector's mind/insanity.
If you work out, you can tell by looking at it that it is a bodybuilding Baggy-T, not a "fat and tall" man's t-shirt like you mentioned. It's by House of Pain, a known bodybuilding clothing store. If we look at hockey for example, "hockey clothing" would amount to a jersey, hockey shorts, skates, or a helmet like you said earlier. In bodybuilding, "bodybuilding clothing" amounts to Baggy-T's, weightlifting belt, etc. Now if it were a pair of socks or underwear then yes the argument that it is weird would hold ground, but that's not the case since what I bought is sports memorabilia unique to the sport and worn by by the athlete.
