Curb box - number of turns = size of valve????

Working on a problem earlier today and a guy I work with said that he can tell the size of a curb box (buried) valve by counting the number of turns it takes to close the valve. For instance, 20 turns = 4" valve.

I've never counted before. Is this true in your experience?

I've never heard of anyone counting turns on a valve before.
Now I have.

Do you think that could mean how many times you stagger when you are turning the valve.

I have not done it for many years, but 20 or 24 turns is about right. The real function in counting was so you could tell whether the valve was completely closed or if was hung up on debris in the seats. When you get to a 12" one, you sort of wish you had a power key.