Thought Experiment

What would happen if you were to fill a one-quart plastic bag with 3-oz tubes of toothpaste plus one 4-oz tube of toothpaste, and try to take it through a TSA checkpoint?

By my reading of their guidelines, the screener would confiscate the 4-oz tube “for security reasons” but let you through with a one-quart bag almost full of 3-oz tubes. The screener would probably also look at you weird, but that’s not in the guidelines.

Assuming that a passenger could completely fill the plastic bag with toothpaste tubes, and that the packaging component of the tubes had negligible volume, that means each passenger is allowed to take up to 32 oz of toothpaste in his carry-on luggage, as long as it’s been partitioned into 3-oz tubes. (OK, 10 3-oz tubes and one 2-oz tube.)