I know. There is a huge element of how well you test in a person's level if success in academia. Some bright but not exceptional people seem to give you exactly what you were looking for, where some really sharp students get completely side-tracked and end up on wild tangents.

I have always been nervous of the take home test because I know there is tons of collaboration on them. While this can be a good thing in a productive work environment, it is useless if one is trying to assess whether the student actually knows and understands the material.

The idea of a mark split is an interesting one.

I do know people who I consider very intelligent who operate on that slow burn style. You get an excellent answer when you finally get it. Hmmm.