A question of resolution 720 and 8**

[Backflip]

I'm convinced that the quality would be better
if the 3CD were 720 instead of 800 width.
Because the kbps/sec rate would be higher than it is with 800 width.
There's no DVD higher than 720 width.

Yep but there are many upsampling filters/scripts with which you may achieve the resolution higher than dvd res without producing artifacts, and then the rips with res like 800xXXX looks way better than the original 720xXXX.

This is all assuming you're using square pixel and same bitrate (1,700+ I guess). From what I've read about this the information is incorrect since for one - DVD's have a max of 720 resolution, so you're losing pixel detail information to begin with

Maybe someone could give a more technical explanation of why exactly

What are these upsampling filters/scripts btw?

[CWR03]

It makes perfect sense that using a higher bitrate/frame size with a limited filesize can bring down the overall quality of a file. What doesn't make sense is how you can "upfilter" from 720 to improve an image. Conceivably it might make some improvement with anamorphic widescreen where the 480 height is compressed to add the letterboxing on some 1.85:1 images, but if you stretch both width and height there's only the chance of distortion, which is why you'd need an upsampling filter.