Yes I think this is the crux:

> Trust in the developer is required ... but it is likely the case that developers are incentivized to illustrate that they are reliable, careful and trustworthy -- and that should strongly encourage accurate test result signing

100% guaranteed you're going to see "oh I just made a stupid typo that broke one test but I can see what is wrong so I'll just fix it and use the previous test results".

Also since it's entirely based on trust anyway I'm not sure what additional benefit signing gets you. I don't think there's really a way to prove you ran the tests.

Either way, all my other points still stand. CI isn't going anywhere.