Ed,

 If I understand the possible location of the hot spot properly I have a suggestion. Since the rotors are new (and perhaps near max width) you might have had a side seal that was near the max allowable length that was wedgeing against the corner seals when heated. If the housings have been compressed/heat cycled as we know they have it could account for the "tightness" you noticed in the engine. The hot spot probably occurred right away but the toughness of the TES o-ring masked the problem? The side seal would only pinch at the smallest point in the housing.

Just a thought,

Bill Jepson