The theory wouldn't hold to justify the run up in prices during the housing boom, or the rent/purchase disparity now. But in the long run, I do think that pooling could be used to allow larger amounts of credit to be extended to people without a huge increase in risk. I could see this leading to a one time, permanent increase in the value of leveraged assets like real estate.

Keep in mind - it might have been a plausible explanation for why real estate jumped 25% when historical trends would only have forecast a 10% rise. It wouldn't explain a massive run up (2-3 fold increases in housing prices over the course of 5 years). The housing boom was eventually driven by irrationality and corruption, which may have completely obscured a smaller but more rational increase in prices resulting from a legitimate technique to pool risk.