I've had an interesting set of attempts in the last day with mine and have been reading many posts to work out the best approach!
Basically, I was stuck going out last night after 2 days of heavy-ish snow. The 159 (with 19s) was seemingly spinning, juddering slightly and 'locking' (even under gentle revs) due to compacted ice and I couldn't even get enough traction to move off more than a metre! Then my dash lit up with various Ice warnings and disabled all my VDC/ASR etc
A bit embarassing as after several failed attempts I had to get all the family out and into the wife's 1.2 Corsa (courtesy car)
This went off with out any issues of course!
When I returned, I shovelled some tracks clear and got rid of the compacted ice, put down some rock salt and tried again. Much better and moved off a few metres but then started sliding. The "VDC disabled - consult manual" warning was still on though.
Next step - I ignored my manly instincts and reached for said manual coupled with some threads on here. I tried a third time, this time turning off the VDC but leaving the ASR on and off she went with no issues at all. I did feel as if the computer was being more 'controlled' with throttle response/power so maybe the CPU realises the conditions
Anyway, once onto the more cleared main roads, I switched the VDC back on and my warnings disappeared. Rest of journey was trouble free so here's hoping.
I agree that the premium summer tyres are the issue here but temporarily turning off electronic aides and adapting driving style will also help. Just ordered some autosocks too just incase as I'm sure we're get more of this Arctic blast.
Oh, the irony of having a Sport
wagon with a ski-hatch