I wonder if he ever regretted jumping to the WBF. 
Politically, it all but destroyed his chances of ever being Mr. Olympia
But it was good money... and one has to pay the bills.
Yes, it was a political mistake, but I don't think Berry De Mey would have won the Mr. Olympia regardless. I think you could make an argument for him coming 2nd in 1988, after Rich Gaspari or Lee Haney - depending on whether or not the primary judging criteria was shape or conditioning. The judges had no problem giving the title to Haney, despite him not being anywhere close to conditioned as Gaspari and De Mey.