The RealTracks have the full playing style of the musician; the "playable" part is played from a MIDI segment, so any "live" expression can't easily be included. For that short part you get the slightly more robotic sound of a MIDI player, rather than the RealTrack.
OK so if I understand you correctly, when you add Playable Real Tracks
you are adding the standard RealTracks plus a midi component (which is the 'playable part')?
The two are blended together?
I was hoping that the part that was played (midi) was then somehow
turned into an audio track and merged with the RealTrack,
so the net result would be all audio.
Perhaps this will happen in the next version or sometime in the future?