"In that respect people do make good buys when the house goes up value: It means they largely locked in their housing costs at a lower rate and their insurance is paying off."
No, the rent vs buy question is a lot more complicated than that. Renting can be and often is financially better even over the long term when house values are appreciating at historic rates, or even faster. As just a couple more factors to consider, property tax and maintenance costs go up as property appreciates and along with inflation, respectively. Remember that renters don't make any downpayment, and that that money and early term savings over mortgage can be invested in assets that tend to grow at rates much faster than house values.
And the rent vs. buy issue that's hard to resolve is for comparable homes being rented or owned. The fact of the matter is that many people buy more home than they need, when they could have happily been renting a smaller home, and trade up only when necessary, skewing answer more toward side of rental being more cost-effective. (You could do this with a house, too, but people tend to buy more house than the need at the time, perhaps partly b/c of practical difficulties of selling a house and the large commissions that get paid to brokers.)