I've soaked mine over night many times. When I get up and start coffee, I turn on the gas and them cook about 10 min... awesome and so much better than rolled oats.

I've actually cooked large batches and reheated. I didn't think reheated oatmeal was bad and I'm pretty picky about the quality of my food. Reheated steel cut oats are nothing like reheated rolled oats.