Off-Topic Forum

I just read a blog post from a link on this site.  I hate to be rude and tell the guy that a certain team didn't wear a certain cap he thinks they wore in a certain year, but he's basically claiming to know more about said certain team than the Hall of Fame curators.

.It's not rude if it's an error. The writer will appreciate the correction, hopefully.

If you don't want to do it in his public comments, then privately.

Yeah I would say privately if that is an option

I would do it privately. Doing it publicly makes too much drama if he/she takes it the wrong way.

As a blogger who links through the site, if I made a mistake I'd welcome a correction.

I've had people point out mistakes in the comments. If you do it tactfully, then the person should be happy to gain a little bit of knowledge. If you come across like you're making fun of them for not knowing something, they won't take it well...I would not take it well. 

When he corrects himself, he can simply label the original ERR and COR for the updated one. Speak his lingo, he'll understand.