I have found many times that to get unstuck, you turn of TC which is kind of a contradiction. This has happened to me a few times.
Sometimes a bit of wheelspin is desirable.
Also if you are sliding a bit in snow with TC off, you can control it with the throttle.
With the TC/ESC on, it will cut the throttle and apply brakes.
This can cause you to go in a direction you didn't intend to.
You can easily try this yourself. ( if you have snow )
BTW, there is a good thread going about the subject in the 2011 section: