Yes, your manager was an adept politician. I'm glad he was able to handle the issue without alienating you. However, this is not evidence that an honest rapport

Yes, your manager was an adept politician. I'm glad he was able to handle the issue without alienating you. However, this is not evidence that an honest rapport existed; in fact, it's evidence of the opposite. If your manager was being honest, he probably would've mentioned the performance issue, that it never should've happened, and that it was a frustrating experience. Instead, the manager made a political calculation: he a) wanted to maintain a good reputation with you, his report, because that makes his job a lot easier, improves his advancement opportunities, etc.; and b) valued your skillset sufficiently that he didn't intend to risk it by dwelling on a failure that he understood you were probably already aware of. His response to you was absolutely political in nature, and not an expression of his honest feelings. The fact that such responses occur is the reason that trepidation is apropos for such meetings.