I am new to your site but have really enjoyed looking over your excellent efforts here for some time and look forward to contributing.
In reviewing commentary on the shoe artifacts it was disappointing to learn that the 'shoe' may not fit after all. Be that as it may, and with great respect for Tighar's conservative approach, a review of the photo available in 'Shoe Fetish, Part III' of February 2, 2004 "The Two-tone Heels" does suggest that there may be an error in the shadow analysis and the attaching "two tone" heel hypothesis as well:
Consider the profile of the heel in the far shoe and the observable perspective of the near shoe sole. Tighar's shadow/line analysis shows a heel outline that is much lower and wider in profile than its mate; the line analysis also suggests a heel bottom (near shoe) that is turned further toward the observer than the plane/perspective of the corresponding sole would allow.
Of course I've not done all the analysis that Tighar has, but by experience it is suggested that focus on 'shadow effect' in old photos can lead to neglect of other details - like the far shoe's clear outline. The profile of the far shoe offers an excellent scale for comparing heel height, and the perspective of the near shoe is well supported by the visible sole. By these observations the bright portion of the near heel becomes normal as the heel's 'wear' surface.
The near-shoe heel thus is narrower and taller than suggested by Tighar's shadow analysis line-drawing. Rather than a split-pigment heel as has come to be suggested, the bright area corresponds to the normal width of the heel wear surface more clearly than it would to a light-pigmented section of a wider heel. The shoe might then just fit...
Perhaps this will be useful in some way, although the shoe concern may pale in the long run anyway given Tighar's robust focus on the reasonable hypothesis of Gardner as landfall and on finding the undeniable artifact: the ruined Electra. These observations are offered in case Tighar's reconsideration of the shoe becomes worthwhile.
As to the split-pigmented heels - has it been determined that such a product existed? Perhaps I missed something in the material. The photos of the oxfords (not the 'spectators') in general are more suggestive of heel replacement, as earlier believed. The 'cat's paw' heel is of course also a long-standing common replacement type. Earhart appears to have been practical in terms of her working attire and attitude around the airplane and having sturdy shoes re-heeled (and sometimes half-soled) was a common thing for active folks. In the thirties that was as easy as dropping into a corner shop for a $3 job, still common at $6 or so when I was a youngster in the 60s and early 70s. While my own 'walk' in aviation may not be so relevant, some experiences may be common: new 'cat paws' on my working oxfords as a young man surely made walking up the polished wing of our local DC-3 a lot easier...
All the best and many thanks for much marvelous and hard work done by Ric and the whole Tighar team -
Jeff