I am not questioning his knowledge. He is absolutely right about latency with crossfire. But Crossfire will not be working on VR. It will be even possible to have AMD and Nvidia setup working on VR. Like I said: One GPU for one display.
I asked simple question. Why does Nvidia GPU require 57 ns latency for VR?
Dual GPU setups for VR already been discussed by Valve and work for AMD:
Here is first argument what is happening with Nvidia GPUs:
Secondly: You need as direct control by application of the hardware as you can.
Thirdly: Kepler and Maxwell does not have Hardware schedulers. The last architecture from Nvidia that had such thing was Fermi. And was inefficient, unfortunately. Thats why Nvidia went with software scheduling. To save power.
Next thing is that for scheduling Nvidia went with software, for Kepler and Maxwell. For VR, like I said before, you want as direct control by application over the hardware as you can. With Maxwell and Kepler you have software that controls both the application and hardware. That creates lag. What can Nvidia do in this case? If they are able to optimize the data paths - great. But from hardware point - nothing.
AMD on the other hand have Hardware schedulers in their hardware, at least on Tonga and Fiji chips.