I only use 34/70 for my lagers. I used to ferment at 50F until final gravity is reached, bring it up to 65 for a diacetyl rest, then down to 33F for a week before fining and kegging. My last 5 or so lagers I fermented at 65 for a week, 72 for a few days diacetly rest, then 32F for a week...