I think I should clarify what I meant by "the conclusions are nevertheless trivial." Let's look at the key statement in the conclusion of the study: "Based on

I think I should clarify what I meant by "the conclusions are nevertheless trivial." Let's look at the key statement in the conclusion of the study: "Based on these results, the conclusion can be reached that while unit testing can detect some type errors, in practice it is an inadequate replacement for static type checking." As I've already pointed out, this seems to me an ambitious and over-reaching conclusion, given the scope of the study. But, equally important, it is simply an example of something that was already provable. It should be axiomatic that in principle automatically-generated validation like that provided by static typing should in theory be able to catch type errors not caught manually in a dynamic context, either for reasons of human oversight or human error. In other words, it seems to me that all that has been done here, is to provide a few concrete examples of what was already true and uncontroversial: auto-generated coverage of specific types of validations can be more comprehensive than some human beings will be in some environments and contexts. It has not shown that the perceived benefits of dynamic typing with good unit tests are outweighed by this fact, nor that, statistically-speaking, errors of this type are common enough to warrant a preference of static typing over dynamic typing with unit tests in all contexts.