I hose off my Portland in the shower stall. Of course, I'm single. Not sure if that's a cause or effect.
Anyway, all metal corrodes, but none so exuberantly as iron. Fortunately, there's very little of it on a Portland. My trusty fridge magnet tells me the brake rotors, FD cage and chain have the most of it. There's a little tug from the cassette, but not enough to lift the small cog by itself--nothing to worry about. Other than that, a fastener or two and bearings.
The BB bearings are sealed cartridge, as are the wheel bearings and the headset. I don't know if that's good, bad or indifferent. I've heard unsubstantiated reports of corrosion--presumably bearings--in the brake calipers.
As for chain lube, your question invites almost religious zealotry.
I'll stick to the general advice of "wet" lubes for wet conditions and "dry" lube for dry conditions.
From my experience last year, not even an obsessive amount of cleaning and oiling kept all chain rust at bay. The side plates were turning brown by springtime. But other than some surface rust on a few screw heads, last year's winter bike was none the worse for wear. Except of course for the rims which were worn concave by the brakes.
As for which to ride? That's your decision. I bought my Portland specifically as a winter-worthy road bike, and I'm using it that way daily.
