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In the comments they speculate that the bearings themselves aren't up to the task once they hit higher temperatures, and keeping them cool is the engine oil itself so if oil temperatures aren't kept in check it's the bearings themselves that start to fail.[/QUOTE]
Interesting article. A quick google shows that modern car engines use an aluminum-tin-silicon alloy for crank bearing (coating) which in the tin-eutectic type (matrix types have melting points of 650C (1200F) has a melting point of 230C (446F). Oil temps in the hydrodynamic film however can reach 180C (356F). Do auto crank bearings have matrix type coatings or tin-eutectic? Found some evidence that it is the later. Lots of head space in any case.
Low or restricted oil flow causes heat; heat kills bearing seems to be the kill chain. Hence why that pressure sag near red line always scared me.
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