A friend of mine with a MacBook just showed me this:
If the battery is removed from a MacBook or MacBook Pro, the computer will automatically reduce the processor speed. This prevents the computer from shutting down if it demands more power than the A/C adaptor alone can provide.
WTF!! So the notebook requires not only the power from AC but also from the battery to work at its full potential?
If you have your MacBook plugged but with an empty battery, does it run at a slower speed?