Careful what you assume about block heaters. They're basically just enough to keep your oil in liquid form and stop your block from freezing. They do not keep the engine anywhere close to operating temperature, and it still takes as long to warm up the car as it does in normal conditions. They're not a "jump into a warm car" scenario by any strecth, they're used to stop the engine from freezing and make it a little easier to start - unfortunately you still have to wait for hot air.