Yes, you are correct: http://support.apple.com/kb/TS1909 http://support.apple.com/kb/TS1909 At least, that is the way it is supposed to work. I've been throug

Yes, you are correct: http://support.apple.com/kb/TS1909 http://support.apple.com/kb/TS1909 At least, that is the way it is supposed to work. I've been through a few batteries that were replaced under warranty free of charge by Apple for premature failure. I've noticed that one of my 4 MagSafe chargers is not charging correctly any more even though it can power the computer just fine. It took me a while to figure out that was the case as I kept incorrectly concluding that the problem was in the battery. There have been reported problems with the chargers failing in this way. I think that because a modern laptop can now have intelligence in the charger, the battery itself, and the power management functions of the laptop, we are seeing problems that are hard to debug.