Keying off of the sentiment raised by BearFlag concerning the drivers, is there a consensus forming about whether the Surface dock will ever support two 4K monitors as was promised?
I've got all of the latest firmware updates and the latest Windows 10 build installed (non-Insider, mind you) and the dock still does not work with two 4K monitors attached.
As I have posted above, this is further frustrated by the fact that the Surface Book's engineering made the built-in mini DisplayPort difficult to reach with a conventional mDP cable when the dock is attached. However, with some shaving of cable connectors, it is possible to attach a mDP cable to the Surface Book base while the dock connector is attached. Nevertheless, this does not resolve the problem and the inability to power two 4K monitors remains.
I'd really like to hear from anyone else who has two 4K monitors: is there any magic incantation to get this to work? Frankly, I'd like Microsoft to explain how they felt comfortable making the advertised claim that this supports two 4K monitors. Certainly somewhere at Microsoft (in a QA lab perhaps?) this was set up for testing? How was it done?