I had no idea such a simple question would spark off such a deep and interesting discussion!
I've seen a few Kuroda videos, and have never been less than awestruck. He looks incredibly relaxed as brings the move to a finish..there was a tv show here a few years ago wherein he was interviewed and demonstrated some of his non-sword tricks as well as his kenjutsu. Please excuse my ignorance - what's his background? Presumably not all in sword?
Actually, my 'form' problem is this: I find it much easier to control a heavier bokken and cut straight than a lighter one. Which makes me think that I am possibly applying too much muscle...although I am definitely trying not to, and strive to drive the movement from the hips and knees, not physicaly from the arms. I'd welcome perspectives....