Morris Dovey wrote:
....
Afterward I wondered if a catenary with that same 1/8" chord height
might apply more even pressure...
....

OTOMH, don't think so (if I understand the question).

_IF_ the caul were perfectly rigid, the force would be distributed
normal to the surface uniformly between the two ends irregardless of the
shape.

The real-world difference is how much flexure is in the caul and the
mold and how much bending there is between the applied pressure points.

(At least that's the way I initially see it w/o actually writing the
free body diagram...)

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