Re:Polarisation / Screen flicker (Score 1)

You might want to check out this paper:
Implementing Multi-Viewer Stereo Displays

I've seen the system working with four users, each having their own view, and it works like a charm!

Abstract:

In this paper we describe our implementations of multi-user stereo systems based on shuttered LCD-projectors and polarization. The combination of these separation techniques allows the presentation of more than one stereoscopic view on a single projection screen. We built two shutter configurations and designed a combined LC-shutter/polarization setup. Our first test setup was a combination of mechanical shutters for the projectors with liquid crystal (LC) shutters for the users' eyes. The second configuration used LC-shutters only. Based on these configurations we have successfully implemented shuttering of four projectors to support two users with individual perspectively correct stereoscopic views. To improve brightness conditions and to increase the number of simultaneous users, we have designed a combined LC-shutter/polarization filter based projection system, which shows the most promising properties for real world applications.