Explain the phrase "Oh, He is smart like my shoe" - Chivalry

In Chivalry: Deadliest Warrior and I think also in Chivalry: Medieval Warfare, the Knight has a taunt phrase where he says "Oh, He is smart like my shoe!".

Does this have any deeper connotations than what is immediately obvious? It seems fairly nonsensical. Perhaps that is the point?

I suspect it is an insult - his shoe would be an inanimate object that isn't smart at all, lacking any sort of brain, so saying that someone is smart like his shoe is implying that really, they aren't all that smart at all.

Shoes can be 'smart' as in, Oh those shoes look smart. The wit is the irony of the beginning of the sentence "You are smart," (compliment) to finish as "like my shoe!" (insult comparing someones intelligence to an inanimate object)