Yep, I do that; a couple of wraps of plumber's tape on both threaded surfaces of the bottom bracket cartridge, then generously grease the bb shell as well. I usually remove/replace the bottom bracket 2 to 3 times a year to prevent any seizing and to chase down the eventual creaks and pings that irritate the heck out of me. I also remove and lightly grease the seat post per noglider's recommendation. As hard as I am on the mountain bike and/or road bike, it's the commuter/cx that gets the worst of it with the weather and elements and often sits in the rack at work un-cleaned and wet after a morning ride in the rain. I think commuter bikes get hit especially hard for these reasons and need more maintenance.