I could possibly see an option for variation creeping in and that is this:
1] In Vegas you have more control over the variations of CBR, VBR and Max and Mins.
2] In DVDA you can adjust and SET the Bitrate – period! Often this is futzed around with to get MORE onto the DVD platter, but what it also does is reduce the bitrate for noisy and often needed detail.
Taking THESE 2 views into account I could see a scenario that making a render in Vegas could actually be superior to DVDA! But that’s really a tight call.
Now, in the greater scheme of things, and staying well under an hour play time, the 8mbs DVDA default COULD very well mostly suffice. But, big but here, getting to play with variations and at the very points where they COULD count could possibly make Vegas appear less than competent, where in actual fact, Vegas is doing a far more complex and intelligent process than DVDA was ever intended to do.
If you ARE going to do this comparison, you really do have to compare eggs with eggs and not eggs with apples!
Point in case here: Recently I prepared a DVD-RW test of some work. It is very noisy and gave my Sony STB a bit of headache. Yes, I prepared all in DVDA and at 8mbs. I decided to reduce the bitrare to 7mbs – no real science on my part, just a “hunch” to get thing to play without spluttering. It worked. But I knew it would work, so I reduced the bitrate. This was NOT about getting more onto the platter, it was me saying ok, I got TOO much noise here for this STB so I need to reduce the bit-rate. What it would ALSO have doine was to reduce the detail – which I would be unaware of – onto the Bravia 40″ screen.
OK, I got me armour on now . . .
Grazie