Generally, You Taught Me That is a Stock Phrase
directed at a mentor. The pupil is exhibiting, and thankful for, a skill or a value that the mentor taught him, and wants the mentor to be proud of him
In a more dramatic use, You Taught Me That is directed at a former mentor, in a situation where the mentor and the pupil find themselves on opposing sides. It could mean one of three things:
- The student defeats the mentor using a trick that the mentor had taught him.
- The student is sticking to the values that the mentor had taught him, before the mentor's Face-Heel Turn. In this case, the mentor is a Broken Pedestal.
- The mentor had been a bad example to the student, usually unintentionally, since the mentor's actions didn't seem to live up to his words. This is what prompted the student's Face Heel Turn, and he is currently exhibiting the same flawed behaviour that his mentor regrets. Expect a lot of guilt on the mentor's part.