Does the book "A Classic Talk" mention that Mencius took the method out of context?

no.

A Talk about Classics is a book that introduces China's traditional cultural classics, including some comments and interpretations of Mencius, without mentioning Mencius' out-of-context approach.

Mencius was a philosopher, thinker and educator during the Warring States Period, and he was a representative of the Confucian school after Confucius and before Xunzi.