Been following the thread-----I would have to disagree on this, I think Davis is merely stating a fact about incident metering in general, IMO. An incident reading in full sunlight can't account for the shadow area in that same full sunlight. Since an incident reading is based only on the intensity of the light falling on the subject, it stands to reason that all the various reflective surfaces would be properly exposed, only if they are all receiving the same illumination. This can't possibly be the case in a high contrast lighting such as full sun with distinct shadows. As it's been stated, I think, averaging the sun and shadow reading is a step in the right direction, but by itself, the full sun reading can leave the shadows hugely unprotected.
Originally Posted by markbarendt
In the attachment with Ross---in A, the meter is placed in a full sun area, the shadows are under exposed; in B, it's placed in a full shade area, the high values are over exposed; in C, the meter is placed in an area that is not full sun nor is it full shade, the exposure is about right; and in D, the exposure is based off an in-camera reflective reading, the exposure pretty much matches that in C.