Well we need to square up on the assumption.

My goal in the OP is to simply to place the face, in this case I don't really care about where the rest of the exposure falls.

So I did a down and dirty test, in camera JPEGs uploaded to Flickr

http://www.flickr.com/photos/3005681...7626728718220/

Like the example in the op the subject is in open shade camera looking out of the shade.

Used EI 400 and f/5.6 for all shots.

Classic metering got 1/250

Follow the nose 1/320

Meter the Main got 1/400

None of these methods came close. None had blown highlights on the subject.

From there I shot 1/500, 1/1000

At 1/1000, two stops reduced exposure from classic, the subject is starting to look a bit like the op example.

Could probably go 3 stops.