Actually, GW, winter tires are not solely designed to be driven/ridden in snow. They typically contain a lot more silica than A/S tires to keep them soft in lower/freezing temperatures - as we all know, the more pliable the tire, the better the traction. So they provide a lot more traction than all season tires in cold weather on dry roads.
Winter tires also feature different tread patterns, with multiple cross section cuts called lamels, that spread under load and bite into the surface (slush, snow or ice) to add more traction.
Many riders in Northern and Central Europe, that I have seen, run winter specific rubber - especially those delivery guys on scooters. In some places, they even stud those tires, but that is illegal in most countries unless there is snow covering the roads.
Many EU countries have local laws that mandate the use of winter tires from late fall until early spring. Not sure how that applies to motorcycles though, or Switzerland for that matter.
I think that if you limit your riding to dry roads in the winter, and take into account the reduced amount of traction due to colder, less sticky tires, you should be fine keeping the bike upright. The legality of that is something you will have to check locally.
'09 DL-650A with stuff
'05 Ural Tourist with stuff :cornut: