Smarty wrote:
I was / am an electrical engineer for 40 years before retiring, and have
never, ever heard of such a design which is deliberately engineered to
become more sensitive as it gets older. This concept for a circuit
breaker is pure nonsense in my opinion.
....

That's what I think, too...

I can see there being an issue of a sizable _de_-sensitization w/ time
if there were some physical process going on in the bimetal or similar,
but I'd be quite certain if it ever was an issue it has been resolved
long ere now...

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