George Lendich wrote:

Ernest,
I agree with your statement we tend to overengineer everything, I believe through ignorance and I don't think that's too critical of myself and others, but before we challenge those more experienced, I think some experimentation should be involved.
It's your idea, so what about testing these spring clams to pressure (and over) and over extended time to see what the outcomes really are!?
George ( down under)

GOOD point, George.  Nothing like real data vs theoretical posturing.

It just so happens that I've been running just such a test for a little over 7 years now.  Literally thousands of heat cycles later, and they're still going strong.  I've run them for extended periods in the coldest and hottest weather that North Carolina has to offer.  I've even pulled them off and reused them when one of Dodge's crappy heater cores cracked on me. I've got some assistants running tests for me up in Canada so that they can be exposed to colder weather, and a few in Texas and Arizona so that they can see some real heat.  So far, they just keep going like the Energizer Bunny.

Lynn and many others have forgotten more than I'll ever know, but there's real world experience staring me in the face here.  I  don't see anything that indicates the springs aren't up to the task, and lots of evidence that they are.