Thanks--I fully plan on just pulling off the core DTS track any time one is available, as that does make the most sense when it's possible.
I guess I should have clarified that I was referring to discs with multichannel LPCM or Dolby TrueHD tracks, since in the former case there may or may not be a lossy surround track at all or it may be low bitrate, and in the latter case the AC3 stream tacked onto the DD-THD stream may be encoded at a bitrate lower than the 640 kpbs max allowed for Blu-ray. Also, my target medium is BD25, so unfortunately I can't use the superior FLAC lossless compression.
