Here in Toronto there are many days in the baddest parts of winter where all roads still dry up, especially when it is well below freezing point. Let me tell you my friends that there is nothing the Tiger likes better than gulping up dense cold air. And there is nothing like a cast iron V8 to keep a rad heater working.
The main rule I have is that the car is never fired up unless it will get a good run to bring all fluids and mufflers at full temperature. I am quite picky about that to the point where I push the car in and out of the garage if I need the space. I try to use the car once every week and a half throughout the winter.
I have been parking the car on a vapor barrier plastic sheet laid over a concrete floor in an unheated wooden garage. I keep a fan running in the garage to move the air around. The cars is covered with a dust cover only.
Roof shrinkage has not been a problem with the two replacement roofs I have had since 1991. Actually, shrinkage has improved them. Some winters the roof is up, but more and more I have been fitting the hard top on. My Tiger came with its original canvas roof which had twisted the metal frame over the years it was left folded away. I had to take it apart and re-weld it correctly to fit a new canvas.
My thoughts on winter, cheers, Gilles