Thank you very much for explaining the situation with this feature of RB. I have to say it is one aspect of RB that drew me to going back to using it but I couldn't understand the how RB could do this job with RealTracks and not then use a similar process for working with Midi. As you say, this would be a fantastic selling feature because the resulting midi can be exposed to such a wide range of synths and midi effects (which is really what I was looking for).
So, once having auditioned a suitable style that contains the part I am looking for, I now have to load this style in order to generate the part. But now I have to keep track of the original style and any other parts that I might use if I require any of these for re-generation. This is perhaps not too big a problem and where the Comments feature would really come in handy.