He participated to that effect briefly (but only briefly) in the deeeiscussion about deep stops on ScubaBoard. After a few comments he was through.
I would think so. He has nothing to gain by engaging in debate about it. Ross Hemingway did debate it and ended up making himself look completely ridiculous in the process. Wienke would have seen that and realized that he didn't want to damage his reputation in the same way.
The debate was waged nonetheless. I don't think there is a serious technical diver on the planet who still believes in RGBM or VPM regardless of whether Wienke engages in the discussion or not. There are still some computer manufacturers out there who are licencing RGBM and he's still making money from it.... It will be interesting to see what those manufacturers decide to do when the duration of the contract has expired. It should be clear to all of them by now that they bet on the wrong horse...