After reading the owners manual and a multitude of posts telling me to expect better MPG after the first 4000 miles, I have ask this question: (yes, I realize this has been touched on in several other threads.)

What percentage of the break-in period is car and what percentage is driver?

Does the FEH/MMH actually run at less than optimal effeciency during the break-in period in order to condition the battery and "take it easy" on the new engine?

Or is this just a myth supported by the fact that drivers get better at taking advantage of a hybrid in the first 4000 miles? Any Ford service techs care to chime in with the facts?