This is partly inspired by a comment Susanna made on an earlier post.
On my first job after engineering school I met a couple of men (a steamfitter foreman and an inspector) who had decided to become engineers themselves. They were taking calculus and physics at a local community college and having a hard time. So in return for a lot of free meals I whipped them into shape.
They had two totally different styles. The fitter foreman was Mr. Abstract - 1+1=2 was fine, but no story problems!. The inspector was Mr. Concrete - give him an apple in each hand and he'd know how many he had, but 1+1 would throw him. Well yeah, that's an exaggeration, but in fact I had to present things in drastically different ways to get the concepts across.
Ultimately both got A's in both classes for both semesters when I helped them. But in a real classroom one would probably outperform the other, with the decisive factor being who they drew for an instructor.
So which one was smarter? Does one of them belong in a 'slower' class?