I don't have a dick to give - You try to pitch in but you’re just guessing and got no fact

You try to pitch in but you’re just guessing and got no facts. You’re like a blind man who says he’s a chef.

I don’t have a dick to give, I just have a guess.

I don’t have a dick to give, I just have a theory.

I don’t have a dick to give, I just have a feeling.