This is something that I have never done, until some recently. Palmer does advocate that at the point where yeast starts to slow down (and they are not generating much heat) you raise the temp to keep them going. He also talks about raising temps for a few days for a diacetyl rest, even for ales. Most of my brewing life I have just let the beer ferment in a cool basement for 2 weeks...though some places I lived did not have a basement.
Of my recent beers...I have an Oatmeal Stout that I kegged at day 6 and put in my beer fridge, and it is a good beer...I have a Porter that after 7 days in the fermenter, I moved it to a 70F room for 3 days then into the beer fridge, and it is a good beer...I have a Pale Ale that has been chugging along in my basement around 60F due to cold weather and furnace issues and I took a reading today and it is down to 1.010, below the projected 1.014. I am not sure I will ever really understand yeast.
