"Michael A. Terrell" fired this volley in
m:

Sigh. The contacts are a hell of a lot larger than the die in a
semiconductor, which may only be .001 square inch.

They're also ignor(amus)ing (gotcha, Iggy) that the contacts are not just
floating alone in still air. They're welded or brazed to larger metal
pieces which form the armature or fixed contacts in the starter. Those
metal parts also dissipate heat (and conduct it away from the contacts
very well, by design).

Someone, probably a long time ago, kept the heat dissipation needs of
those parts in mind when they designed the contactor part of that
starter.

When it's working properly, I'd expect to see a larger drop across the
heaters than across the contacts.

LLoyd