So from the original homeowner's perspective, it really sounds more like a fancy sort of home equity loan than an actual way to sell your house.

I guess my "stumbling block" here is that a house — as a tangible thing — isn't divisible; it's always going to be "one house." As such, only one person/family unit can derive direct utility from it... everything else is indirect utility, such as sharing in capital appreciation.

I guess it beats paying interest to a bank...