I think SD is still not being completely clear, perhaps because they don't understand themselves. Back when Roku had an RMP developer that was actually possible to talk to, he explained to me that RMP was only a UI, and that all playback functions were directly performed in the Roku OS. So RMP would be no different than the HDHR channel, sending the media to be played from the OS. That perhaps might be some of the issue, but since I'm not well versed on the programming language used by Roku I might be missing something as well.
Dan
Roku Community Streaming Expert
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