If (as the study says) # of tests is the true correlate then 1. We need some way to compare # of tests across differently-sized codebases, i.e a percentage met

If (as the study says) # of tests is the true correlate then 1. We need some way to compare # of tests across differently-sized codebases, i.e a percentage metric like coverage 2. The fact that correlation disappeared when controlling for absolute # of tests seems to suggest it's still encouraging people to write more tests. Once your org gets to a certain size you need these blunt instruments like minimum coverage requirements because you can't just rely on individual excellence anymore.