I'm going to drink the Koolaid and become one of the Brooksian cult. After dealing with several synthetic ass-hatchet saddles in an effort to find something that I don't think about while riding, I've decided to go B17. Anyway, I've read all the threads about shower caps, plastic bags, blah blah blah... I'm going to be putting fenders on my bike but since I ride in Chicago and plan to be commuting throughout winter, I'm a bit concerned about keeping the saddle in good shape with all the muck I'll be riding through, not to mention the salt they throw down everywhere. When folks are talking about plastic bags, shower caps, or even the dedicated covers, do these only protect the top of the saddle from moisture coming from above? I could see where a plastic bag might be pulled tight enough to protect the bottom. I'm guessing full fenders will keep a lot of spray and gunk from getting on the saddle underside anyway? Do the dedicated covers (Aardvark, etc.) cover any of the bottom of the saddle? Does the Proofhide applied to the underside confer any water resistance? Anyway, your best tips for keeping a leather saddle in top shape under very trying riding conditions would be greatly appreciated.