talk the talk

Edward O. Wilsonの "The Creation" を読んでいます。
It was for me an influential bonding with a biologist immersed in an outwardly small yet endlessly intricate part of Earth's biodiversity. Archer was a professional, and he treated me as though I were one also. He gave me self-confidence. He taught me how to talk the talk of a real research scientist. He didn't care about wealth or fame; he cared about the classification and biology of spiders.
３月３日に "walk the talk" を取り上げたばかりですが、その時の "walk the talk" の印象からすると "talk the talk" は「口先ばかり達者」を直ぐに連想してしまいますが、上記の "talk the talk" の意味はその様な皮肉な意味では無いようです。辞書で確認します。
・Oxford English Dictionary: Speak fluently or convincingly about something or in a way intended to please or impress others.: They talked the talk but when it came to the moment of truth they couldn't walk the walk.

・Collins Dictionary: to speak convincingly on a particular subject, showing apparent mastery of its jargon and themes; often used in combination with the expression walk the walk
この様な意味だと政治家が言う「説明責任を果たす」を連想しますが、長く政治家をやっている人の説明は、やはり私には口達者の印象しかありませんね。