[ajdecon]

> What's the takeaway?

"Unfortunately this tool doesn't exist for blb++, but we should still improve our coding style for this application. Is there another way to improve our correctness testing? If we allocate some time to improving unit testing, maybe we can do this refactor once we have X% coverage in these critical parts of the codebase."

I.e., acknowledge that both goals are valid, and look for alternate solutions to make incremental progress towards both. Finding middle ground is unlikely to be satisfying from either viewpoint. In this example, Dev A isn't getting a quick win from fixing the coding style right away, and Dev B needs to allocate some time to improving testing. But especially when working on big teams and projects, this kind of piece-wise progress is where I've seen most things get done.

This kind of solution might be pointed out by either Dev A or B, or they might need to bring in a fresh pair of eyes if they're both already frustrated. :)