So is it correct that the Yamaha S950 does not have these 'automatic' SA2 voices that react without having to use buttons?

What I'm still missing regarding the Integra supernatural guitar strumming, I can't simulate a quick "up and down" strumming, which I would need for a lot of strumming patterns. I would imagine it could be triggered by pressing and then releasing the keys again and again in a rhythmic way, but this isn't implemented. (There is however the possibility to program a PCM guitar voice that starts when releasing the key, but that would be a different sample then, it should be integrated in the supernatural guitar voice as an option).