"Climbing on sunny winter days is possible and it's the only possibility to have the south face for your own. But you have to be careful with the descent! The normal route down could be snowy and icy until late in spring!"
The south face can be abseiled because most of the routes are equipped with inox spits.
There are several abseil routes; please refer to
Freudig, T.: Klettern auf der Tannheimer Sonnenseite, 2nd edition, 2006
Correction: U can get simple food at the "Tannheimer Hütte". In my opinion it's better than in the "Gimpelhaus".