Comes with a free cryptowall!
Arcaus, assuming you hit punishment and companion exactly on cooldown and there's no overage, 50% CDR gets you just a shade under 5.5 more hatred per second. Assuming he uses MS, 25 * 50% RCR / 5.5 = 2.27, which is how often, as a minimum and on average, that you'd have to fire MS to save the same amount of hatred per second. In higher grifts, you're definitely firing your spender more than once every 2.27s.
Wolf buff might be a difference. But it's in the DIBs category, so it's probably just drowned out.