2-pass encoding when doing CBR output?

[bobcat56458]

Does anyone see any advantage in so far as improved video quality when using 2-pass encoding and working with Xvid, DivX, H.264, & WMV, and using CBR output? I think the consciences when working with MPEG2 is that you do not gain anything if your using Constant Bit Rate encoding, and doing a 2-pass encoding. Does the same hold true with the MPEG4 formats?

[Teegedeck]

Two-pass is two-pass, CBR is one-pass only.

Don't use CBR in XviD, it is very sub-optimal.