At the properties that list gold and diamonds on the welcome board, there are usually five or eight names, and I'm talking smaller Hampton places, not giant resorts.

Hang out at any diamond check in desk, you will see way more then one or two people checking in that day, there isn't any way they would dedicate a desk (or an office at some properties) to it for just one or two people.

There are way more Diamonds in any given Hilton at any time then the percentages indicate.

I also don't believe you can take the number of people holding cards, and translate that into number of people staying at any property, saying that one in every 40 is a diamond because one out of every 40 HH members is a diamond. A person can be an active HH member without going near a Hilton, it's significantly harder to obtain Diamond status without staying at the hotels.