Stable process is cherry pincking thousands to tens of thousands of patches from the current master kernel branch into years old kernel branches, spraying tens of thousands of emails at original patch authors, hoping (With some limited testing on top) that the resulting frankenkernels will still work and all these patches will have satisfied dependencies applied, too.
I don't trust this process very much, and just run the latest stable branch for the latest kernel release, only. Staying with older stable release branch for too long seems too risky, unless you're some bigcorp that can afford the testing required, or you're running some highly mainstream setup that is probably covered by tests done by the stable team, and testing teams they cooperate with.