I did not measure my actual mileage last winter, but it was certainly significant. My sense is that I am lagging a bit this winter. Why? There seems to be more days when there is fresh snow on the trails which makes riding significantly slower. Second I am a bit intimidated by the recent death of a cyclist in town. Plus a few falls of my own have rendered me a bit more conservative. Nevertheless I remain committed to riding all winter.
Why expose myself to the danger and discomfort of winter riding?
Machismo. Hold it buckaroo, isn't machismo a subset of stupidity? Wellllll, yes, I guess. But it IS only characteristic of one gender, and therefore distinct and interesting enough to merit its own category. I estimate that 12.5% of my motivation to ride through the winter is machismo. It would be more, but with PD, that's about all the machismo I can summon up.
Guilt, in the form of remorse for my carbon footprint, combined with my desire to avoid guilt should I cause a car accident, drives a rather hefty 12.5% of my motivation. And I wasn't even raised as a Catholic! Sheesh!
Moving to positive reasons for riding, we have 15% sheer fun (and thrills). A masssive 25% of my motivation comes from the all-important role exercise plays in of coping with Parkinson's Disease. Finally, we have the savings on the cost of monthly car payments, gas, insurance and clever bumper stickers coming in at a solid 25%. Disclaimer: All elements involved in this chart are estimates; your mileage may vary.
Have I eliminated the infernal combustion system entirely from my appointed rounds? No. I still rely on my wife and others to chauffeur me at times. And I still climb behind the wheel on rare occasions. But I have found that I can take care of an enormous amount of daily errands, such as going to the bank, the Post Office, even moderate grocery shopping, on my bike. Sure, there is risk, but what the hell, I've already got Parkinson's Disease. My riding days are numbered. I can't let a little thing like Winter get in the way.