This may be some urban legend as I don't know how it would go unnoticed unless he was jerking under a table for a few seconds to get players reactions. But the theme here is that he's attached to many weird stories.
Matt Light has asked the same question. He mentions for whatever reason, Hernandez got away with stuff.
"
I would say that it's really safe to say that Hernandez was given a longer leash to kind of do it his way than most players."
Former Patriots tackle Matt Light recounts his locker room run-in with troubled former Patriots tight end Aaron Hernandez
985thesportshub.com
Welker also found out very early on:
"In an anecdote near the bottom of a longer report, it was mentioned that Hernandez was at the team facility trying to watch film, when he grew frustrated at not being able to operate the equipment. Wide receiver Wes Welker walked by, Hernandez asked for help, and Welker replied: “Rookie, you figure it out.”
"According to Shalise Manza Young, Hernandez’s reply was “f--- you Wes, I’ll f--- you up!”
Stories continue to accumulate about the signs in Aaron Hernandez’s background, stories that paint a more complete if complicated picture about his character.
www.nbcsports.com
Welker warns Lloyd regarding Hernandez:
"I just want to warn you that (Hernandez) is going to talk about being bathed by his mother. He's going to have his genitalia out in front of you while you're sitting on your stool. He's going to talk about gay sex. Just do your best to ignore it. Even walk away."
"Former Patriots linebacker Dane Fletcher, who like Hernandez was a rookie with the team in 2010, said he and Hernandez had a volatile relationship from the start, exchanging both insults and punches."
This is a guy you cut the first week of training camp. This explains why BB continually passed on talented players because of how much a pain in the ass they can be. Hernandez is the final boss of these types of players.