Thanks for your input guys, very thought provoking. You know bouncy music did exist long time before BMB, for instance Sumer Is Icumen In, an ancient English polyphonic round from the mid-13th Century, which is extremely bouncy to say the least. I think Im inclined to say that BMB were perfectly capable of playing swing-time, or reggae, but didnt think to include it in their writing because they were so busy just doing their own thing. Thats the same for modern composers too. Rachmaninov, who Im sure was very aware of proper jazz and swing-time, again didn't actually write it because he was too busy doing his own thing. But I do like to think that BMB actually did play proper jazz and swing-time etc, but didnt incorperate it into their output because it just wasnt who they were, both as individuals or as part of their society. Beethoven of course officially started breaking into it right at the end of his life.
Reflecting on the Socratic question 'is it better to be the best in one thing, or moderate in many things?' BMB were clearly examples of the former: they were who they were, did their own particular thing, and they took that ball and ran with it literally into orbit. But there were various lesser known composers who were more 'moderate in many things', such as the Baroque composer Baldassare Galuppi. Some of his harpsichord sonatas are literally like Chopin, incredible. Also just as a reflection, I think one must take into account the Jungian global collective consciousness, which I believe can be tapped into as an artist. I really dont think exposure to other cultures is the be-all-and-end-all of creating ground breaking or revolutionary ideas which dont appear at the onset to part of your own culture, quote unquote. Do you really need to be 'touched by African culture' just to put a bit of bounce in your right hand? Really?? don't think so. Surely putting a bit of bounce in your right hand is a natural human thing that all people have anywhere in the word, and at any time..