I have alright tonguing, and I have been pretty lackadaisical in trying to find something to clean it up. My teacher, the great Jens Lindemann uses anchor tonguing, and has recommended that I try it as well. I'd like any comments on anchor tonguing, if you could help. I've started trying it, and it's a work in progress.
FYI, if you don't know what Anchor tonguing is, it's when instead of using the tip of your tongue to articulate, you have that part resting against your bottom teeth, anchored if you will. Then you tongue with the front middle of your tongue.