I was introduced to the philosophy of the 3 principles about four years ago, and it did not immediately resonate with me. A friend rekindled my interest and as a result I have been incorporating these principles into my life on a daily basis for the last three years.
My initial concerns were that this was just another fad, and that there appeared to be little if anything new that was not covered by other philosophies.
To some extent I still believe this to be true, but on a deeper level I know that an appreciation of the 3 principles provide insights not easily obtained elsewhere.
Whilst I may not specifically mention 3 principles in my work with clients it is certainly always there in the background, along with the other knowledge and techniques I use routinely.
In summary I consider this subject well worth your serious consideration.