Ha- Yes, this is one of the rotating yearly threads. Leaving the charger on all winter long is a gamble. There is a very good "maxim" for power electronics. i.e., chargers , TV's, stereo's , computers, etc - "It's gauranteed they all will break/fail at some point in time".  With failures of TV's & stereo's we don't have to worry about collateral damage.  However, a charger failure can wipe out the batteries, just like a computer crash can destroy your data.

Leaving the charger on all winter is OK if it's a "float type" charger. However- you should monitor it on a fairly regular basis. It doesn't take long or much abuse to destroy a battery, i.e., via either undercharging (the charger fails and just stops charging) or overcharging (the charger fails "full on" w/ no regulation). The results are the same come spring time- you will need new batteries.

IMHO- The periodic topping off method is the safest- because you have control and it doesn't require constant monitoring.

The opinion of 10,000 men is of no value if none of them know anything about the subject. -Marcus Aurelius

Al Warner

"All Water is Zalt Water"

http://www.zaltnad.com