Well obviously Patsy had the Capablity of being vicious, why not whack out the more dangerous brother???
And I took Patsy's "he ain't heavy" statement to mean, he didn't have beefs with people, doesn't mean he didn't clip anybody. I could be wrong, there was Bobby Bacala.

"Joe Bananas went after Carlo Gambino, the war went on for seven years..... When guys go to the mattresses, they're not out earning" -Tony Soprano