Do you get more higher the more thicker the joint?

My partner loves to roll thicker joints than what I would consider normal. My jays are closer in radius to a cigarette while theirs are like a .44 caliber bullet. I don't mind this. I love them. But I do always razz them about their big joints. Tonight they said that the thicker the joint, the higher you get from it.

I argued that it burns at the same rate as a small one, so what difference would it make?

They argue if you're burning 1/20th of a joint with 1/2 the weed, it's 1/20th of a smaller amount of weed. But if you're smoking 1/20th of TWICE the weed, it's 1/20th of that larger portion: like getting the same percentage slice of a large pizza.

Help us. Who is right in this friendly debate?