There's really two things here.
Patrick's perception of a "role model" here was, by him, admittedly skewed. The 6' 240# ripped/jacked guy was actually only 200#. As also mentioned, he might be bumping the ceiling of drug-free lean mass at his goal weight. Not easy to get to either, I'm sure Grimek would agree, and Grimek was (I'm guessing) very BB/DB-centric in his own training.
Lastly, his BW program...simply isn't working even in the context of a massive surplus of calories. If it isn't working, change something.
How about this compromise? Weighted dips and weighted pull-ups. Don't forget the back squats.