I've just started doing some lanes on my XTR and I know what you mean. In the dry, the lanes were great fun and not too taxing. Riding on Friday with the mud and grass damp was a totally different, frightening experience. I managed 10 miles before thinking a big off was inevitable and heading for home. The TKC80s were sliding all over the place and at one point I spun 90 degrees in the mud. I still don't know how I didn't go down. Suddenly 100kg 250cc bikes with 10psi tyres and rim locks make a lot of sense!