Thanks for the reply;

I'm a believer in "right-sized" testing, meaning balancing the cost of test creation and updating against the value the tests provide. I believe tests provide the greatest value when they are testing: * public methods * critical business logic * highly reused core logic

in other words, "code for others".

For code that's used for one specific page render or something similarly isolated, I think it's more questionable whether to bother going for 100% code coverage.

The latter category is where I'd like to "trust but verify" with devs permitting them to opt out of unit tests where they believe the code isn't critical, but have some confidence that we would catch code if it became more central and then enforce testing requirements.