I suspect that showing by Ben (and it was an impressive one) was a result of him really stepping on the "gas". I have a hunch that he got some labwork or test results of some sort that woke him the fuck up and he wisely chose retirement.
You are probably right. Though, IIRC the reason he gave at the time he retired was something along tge lines of: he reached his full potential, more or less maxxed out, it wasn't enough to win any pro shows and wasn't going to get better so he retired. I think he specifically mentioned his arms as a weak point that he wasn't able to improve on.