I think a lot depends on the trout species and the conditions in which they live. In the Sierras, there are many cirque lakes that were stocked decades ago with Eastern Brook trout. In most cases, especially at high elevations, the fish in the lakes are starved, stunted, and overcrowded. More catch and kill fishing on these lakes would probably result in better conditioned and better fed survivors.
Again, at high elevations, there are similar cirque lakes with healthy specimens of Golden trout, and catch and release of these beauties is most likely called for.
Rainbows in the cirque lakes also seem to do better than the Brookies, maybe because of cannibalism. Taking a couple for dinner in most circumstances would do little harm.
Cutthroats also seem prone to over-crowding and stunting, although they are such willing biters that it's easy to fish out an entire population (witness the wonderful cutthroat C&R fishery on the Middle Fork of the Salmon -- before C&R came into effect, cutthroat fishing on the Middle Fork was generally lousy).
From these few examples, I'm trying to argue that species, species origin, and local conditions probably determine the benefits of C&R over catch and kill.