I need to get hold of some versions other people have done (MySpleen? or contact people direct) so I can do some better comparisons than just using still shots, I only have the Dr_Gonzo versions so far and the detail is blurred out on those. In my above test pictures I used a 2d smoother which may be the cause of less detail than yours, also the 2x resize that the edgeresample filter may be contributing, I'll try some tests without that filter.
Currently (from memory, I'm not at home right now) my VirtualDub filters are; chromasmoother,2d cleaner,2x edgeresize,xsharp sharpen,lanczos3 resize to anamorphic PAL. I want the last filter in the list to be the scaling down to PAL so if when shown on a PC (or my friend's plasma which doesn't have a native PAL or NTSC resolution) any resizing by the player/screen doesn't resize any artefacts from a sharpen or other similar filter.
When I'm back home I'll post a couple of links to PNG images of the 5-averaged avi's so you can see what I'm working with before any VirtualDub filtering.