Sorry, I wasn't responding specifically to your post, I was just making a comment in general about preventative measures for the "too many short trips" syndrome. If the battery is truly getting a cumulative current deficit due to short trips, eventually leading to a dead battery, I would start with once a week on a battery tender and only put it on more often if the battery discharge message popped-up again.

What you say is very true -- if a battery ever gets run-down, one should not depend on the vehicle system to fully-charge it back up. One should put it on a battery charger, as you say.