Most folks could learn some the the basic skills on their current bike but the idea that you only go fast on a dirt bike keeps them from really improving their skills for this type of riding.
That's the thing you don't NEED a trils bike to practice the beginning skills which also transfer over very well to all forms of dirt riding. Sure the bike is quite a bit different and can make some of the skills much easier but it's note really a necessary item in the beginning.
I do alot of low speed playing on the crf now. I really have a blast pushing through the woods off the trail and climbing logs/dodging stumps, trees & what-not. Teaches some good clutch/throttle/brake control. It's suprising what you can get a bike to do once you get comfortable with all the controls and learn how to use them all together. The height, weight and power characteristics of the crf make it a bit tricky for some really technical stuff.
JOE you might want to look at th Ryan Young trials videos for some additional inspiration/help in fine tuning some of the skills. I actually ride my XR in much the same way since I sold my Montesa to Rich. While it is no where near the same I can still pull of some stuff that fellow rides shake their head at. Trust me when I say it's NOT the massive skills I have but just a little bit of trials "secrets" I gathered from videos, classes and riding with some VERY skilled trils riders that helped me along.