Why - thankyou for the kind invitation Bloke...I shall.
Osu Gar 23 ...Welcome to K4L... you might find this thread interesting!
I cannot claim to have your degree of musical education or ability, but for me it has been a continuum of one to other and back again.
I play classical guitar now, and yes, I am much more protective of my hands. I noodled around a lot as a kid, earned a bit of money busking and gigging R&B as a uni student, and then didn't play much when I was going thru kyu grades, except to take my instrument along to social gatherings.
As I have gotten older, and a few injuries have caught up with me, I have found that really geting stuck into a difficult classical instrument has been a great outlet for that part of me that has been trained by Kyokushin to be constantly striving to improve. And I drive my music teacher to despair as I repeatedly try to explain why Classical Guitar is just like karate.
Like you, I find the concepts are complementary...I use rubato, accelerando, rall. and even the odd fermata in my kata (Oooh - that rhymes...fermata in kata).....and I have no doubt that my kata training has equipped me well for endless repetitions of difficult sections.
The biggest tension for me is nail length! I need my nails for playing, and I am supposed to cut them off for training....AAARGH. Lucky, I am a black-belt, and I can get away with keeping them on one hand and using an enclosed glove when I work with a partner.
If I was a professional musician, I would be much more concerned about injuries affecting the mobilty of my hands.
What do you play? Do you want this to be your profession? I think you can make it work, but you will need to just adapt some things. For example, if I had a professional muso in my dojo, I would have no objection to them wearing reasonably solid gloves in kumite, even in gradings. There are some things not worth risking. But being physically fit is important for all musicians, no matter the instrument, Sosai himself was of the opinion that Martial Artists should play an instrument. So don't let anyone tell you that you cannot do both.
osu - and welcome again!!!