Following an imprisonment approach doesn't seem like a game-winning strategy for a game of this size.
Sure, you are delaying the deaths slightly as the mafia will likely refrain from their night-killing fetishes, at least momentarily, in order to to implicate the falsely imprisoned townsperson and have them lynched as a result.
However, you are essentially wasting two lynch phases on a single person (the first to imprison them and the second to lynch), which renders such a strategy useless and unlikely to accomplish anything constructive.
The only hands that such an approach plays into is those of the mafia, and as the first person to suggest such an approach, I'm going to with johnhughthom; I find it a little off that a player as capable as you would immediately opt for imprisonment without seemingly considering the cons of doing so.
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