Re: Fovea or FauxVR..?
Pretty much, a lot of the limit back then was the graphics quality. Graphics processing was offboarded to the "host" - in the example I worked with, to 4 RISC processors on a board in the PC. So firstly the same strategy is key, don't make the crappy hardware in the visor do the processing. For augmented reality you are going to need to push the processing even further out - probably cloud - to deal with the large database to process application things and give you "headsup" data such as "This is Jenny, you met her at a conference last year, she likes dogs and gin and tonics, looks like she is interested in you" - you can't do that in native hardware.
Lastly they should buffer the display, then all you need to render/update is the bits that have changed.
p.s. I was product manager for immersive virtual reality systems for IBM in 1995.