High-floc strains (English, ringwood, etc.) can almost completely drop out in a couple of days at those temps (esp. with finings). The small amount left will either not be enough to carbonate, give inconsistent carbonation from bottle to bottle, or take a LONG time to carbonate.
Im doing a red ale with OG of 1.071 and using WLP007 which is a pretty high-floc. Fermenting at 68F right now. I was planning on doing at least 3 weeks in primary. May ramp up the temp gradually to 72F by the end.
Im not even sure just how cold my fridge can get! hahaha! Im using a SANYO brand mini-fridge basically big enough to fit one 6.5gal carboy and it's connected to a Johnson Controls A419 digital thermostat. Ive never done a lager with it so idk what its lower limits are without stressing the fridge motor too much.