Honestly, probably not that many people would do what you are suggesting. Truth is, Universal is pretty expensive, and not all Disney lovers are a fan of Universal. Many people go to Disney discount or not. A lot of people book with hopes of getting a discount, but that is not wise unless they plan to keep their trip without one. If you (general you, not you specifically) book a room with no intention of keeping it unless you get a discount, you are doing yourself no favors. Disney offers discounts to fill rooms. If the rooms are already booked, there is no reason to offer anything.
Bottom line, don't book anything usless you are going regardless of a discount or not. If you won't go without a discount, wait until the discount is released and then book it.
I totally understand why someone would get their room booked before any deal comes up. Disney pushes people to do so. I get asked if I would like to book my vacation everytime I go to check for discounts.
The fact is, I can't do it without the Free Dining and I worry that if people book with the idea of cancelling if the free dining doesn't get offered, that it won't get offered because there are no rooms to make sure get filled.
Kind of a Catch-22 situation.
Good luck all.