As an ex-escort, I've had DATY many times from gentlemen who enjoyed the activity. Unfortunately, not many were good at it... Actually, in my experiences, I was amazed at how many didn't have a clue what to do or were going about it all wrong.
I escorted for 8-9 years, and MAYBE 10-15% performed DATY in an enjoyable fashion, less than 5% ever got me to reach orgasm in this way.
It's not only in my professional encounters that this happened but also in my personal ones. Very few men in my experience have an idea of what to do and how.
As an escort, it always placed me in an uncomfortable position, I either had to:
1. Tell the person and then instruct them on how to do it nicely, which could make things very awkward as not many men like to be criticized about their cunnilungus abilities. Or
2. Fake pleasure and move onto other things. I admit that I used this option majoritarily due to negative responses from option 1.
Although every woman is different, there are some key elements or general rules in giving good DATY. I have found a couple great articles on the subject that I wish to share with you all. I haven't read anything so "spot on" as these in ages if not ever. I think it could be very useful to some in different ways.
The articles will be following this post along with author's credit.