It's actually seems like a good idea...something that could be coded into the reservation system without any impact at all on the local properties.

Like an airline standby list, you could offer it up to any guest and the list could auto-sort by elite status. If a room gets dumped into inventory, the person at the top of the list gets an email or text and, say, two hours to accept or decline at the price point offered. If no acceptance, down the list it goes. If it's within a day of check-in, that 2 hours response time could scale right down to 15 minutes or whatever. Simple programming. Probably could be in beta in a matter of weeks.

You could get carried away and actually auction the room at this point, but now you're talking about more complicated software and a whole new can of worms for revenue management to consider...

To the individual property, there's no incentive to do a standby list because they know some random guest will hit the website at the right time and book the room. But to corporate, it seems like a valuable competitive advantage. The higher elite tiers become more valuable at no cost to anyone, and you reduce the chance that your own elites start sampling and enjoying other brands because they couldn't get into their favorite hotel.