From the source capture files I make an anamorphic NTSC resolution huffyuv avi and an anamorphic PAL resolution huffyuv avi, from there I encode the avis into dual layer and single layer sized mpeg2 files for the DVDs. I convert the capture separately to PAL & NTSC because the last sharpen filter is slightly different, the PAL sharpen setting is 20% higher than the NTSC to compensate for the 20% more pixels compared to NTSC.
If I were to convert the capture files direct to multi-pass mpeg2 it would take 27 days processing to make the PAL & NTSC dual layer & single layer DVDs! hence the need for the huffyuv avis that can be directly encoded to mpeg2.

Believe me the computational process is going as fast as it can.