What's gross is oily gritty muck slung all over you backside, feet shins face and might I point out drivetrain.
Which is why I will posit that it's possible to ride a nice carbon bike year round impervious as the frame is to the elements (think what Vancouvers' salt air/road salt does to steel over time and did do to those old glued Vitus frames) and keep it nice if one can mount fenders.
All you will need are rain wheels instead of a whole rain bike.
I agree with this. And I would even ride nice wheels in the winter if the bike had disc brakes. I've had a few rims destroyed by road salt but this wouldn't be an issue with disc brakes. The only thing holding me back from using a road bike with disc brakes as my winter commuter is that it seems like there are no good fender options. The bikes I've looked at so far (Focus Cayo and Scott Solace) have very narrow clearance in the front fork. The bike shops I visited recommended SKS race blades, but they don't offer full coverage in the front so you still get spray in the face.