This phrase is a combination of the two phrases: the smartest guy in the room, and the sharpest tool in the shed. The phrases are practically identical in meaning, so combining the phrases is a move of a literary genius. The phrase: the smartest tool in the shed means the smartest tool in a hypothetical shed.
He’s not the smartest tool in the shed, it takes him a little bit to understand.

He might be the smartest tool in the shed, but that doesn’t make him a good person.
by Gmannetje June 27, 2022
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