That is silly since even though there is not a huge demand for that kind of compatibility, DVD-A discs are reletively easy to make. If you don't need MLP, a DVD-A disc could have Uncompressed High Sampling Rate stereo audio. So they should add a template in DVD-Arch for DVD-A authoring. Of course this should be in there from the best software company in the world that does the best audio apps anywhere.
thanks,
todd