The great Drain Life nerf, looking back

You may have missed it, but a few weeks ago (by now at least) drain life was nerfed.

Drain Life now deals 25% less damage.

This essentially ended the reign of the drain life spec. But why? Was this a pvp nerf? A pve nerf? I’m going to delve into it, and try to figure out why this was so urgent that it has to be hot fixed NOW (well then) instead of waiting for a patch

Of warlock “nerfs” and other patchy stuff

Ok, so I logged in today, and like most warlocks I went straight to the target dummys. What did I find?