When I first began my study in Taika's art, I already had 7 yrs. Experience, and a Yudansha ranking in Shito-Ryu. After 9 months (or so) of studying with Taika, I abandoned almost all of that previous training. I felt that I had wasted my time with it, and (needed) to get rid of the habits acquired during that study. This wasn't a (necessarily) easy thing to do, the longer that habits are repeated, the more ingrained they become. Even after all this time, I can still feel the tendency to want to do (some of) those habits.
When I work with the students that I have now, I can see them (struggling) to modify their own habitual behaviors. One of the more common one's (that they have to learn), is with Oyata's milking punch.
The problem now (LOL), is that the (2) fore knuckles (used for striking with), are out of line with the forearm (bone's) which creates a weakness in the wrist. as one (once again, LOL) rotates the bone's of the first 2 knuckle's, back in-line with the forearm bone's, the pinky (once again) feel's weak, from the fist loosening to align the knuckles with the forearm bones, LOL (and so it goes round and round).