Another voice saying that studs for ice or possibility of ice, regardless of tire width. Wider tires for deeper snow and wider tires for the uneven ruts that come after fresh untraveled snow. About the only thing snow-wise that narrower tires might be better on (IMHO) is not-too-deep fresh powdery snow and loose, unfrozen slush.
I just got back from a ride where the streets are coated with frozen drizzle. School busses could barely climb hills, cars spinning tires even on gentle take off for stop lights. Studs rule. I could climb, stop, turn, even start on hills. I wouldn't have necessarily known it was icey if it wasn't for what footing when I put my foot down (I slowed at stops, and did a semi-track-stand when I could). Yes, you need to be cautious and use good bike handling skills, even with studs. Yes studs cost money, yes they make noise. They probably add some drag (not that I notice it anymore, and snow adds much more drag, so it's just part of winter riding to me). No they don't do anything for snow: but where there's snow, there's likely to be ice.
If you pick your riding days, or can be selective on routes, or don't really ride in a winter climate, studs aren't needed. I generally don't, and do live in a winter climate, so studs on winter bikes. I can't convince my wife, but she just skips riding a lot of winter days.
Last edited by FrankHudson; 02-07-17 at 11:23 AM.
Reason: forgot to complete that last thought