> on the downside seems to introduce additional artefacts It definitely introduces a form of ghosting visible near the rear end of the motorcycle. As for lag,

> on the downside seems to introduce additional artefacts It definitely introduces a form of ghosting visible near the rear end of the motorcycle. As for lag, I can already see John Carmack cringing! There may be an interesting effect though, in that the increase in apparent resolution is quadratic when the increase in computation is linear. Hardware-wise this possibly could be done straight in the double-buffering phase without additional lag if it can be made to race the beam.