It is an interesting idea (practical, no, but interesting). Heads up Displays or HUDS have been used on aircraft for a while and has moved even into some cars. Basically it allows projecting an image of various displays on the dashboard up so the pilot doesn't have to look down (these days it is built into the helmets they wear I believe, in the visor).
Not sure a HUD would do much with our trains, I think the technology of using eye movements to set throttle speed or flip a switch and the like is something a)would be pretty expensive to implement and b)I don't think too many people would enjoy it. I have seen some layouts (usually ho) where the guy literally built a mock up of the cab of an engine, that had controls mapped somehow to controlling engines on the layout, and they had a 'front window' monitor that fed the view from the engine they were controlling (MRR has had some things like this in the past). Obviously these are guys with a lot of space, big layouts and the like.
Honestly, not reason for it, given the size of even the larger layouts here, can't see that being much of an advantage.
