Well, I haven't done that nor do I plan to do it, but have I thought to myself with each resale contract, ok, if get a deal at $X/point, and then decide after a year or two that I don't really want that contract, can I likely sell it without much, if any, loss? Yeah, that math has gone through my head with each resale contract. But, I haven't bought any of my contracts with this being the plan.
That said, I could see this making sense with a small contract where you're not out that much money, are able to secure a really good deal, have a plan to pretty quickly use the points, and then sell it. I could see that effectively being a way to acquire some OTUPs. Of course, it's not without risk, and I'd probably only do that if I was also ok keeping the contract longer to ride out any ups and downs in the resale market.