[rincewind]

No, it's not about the "optimal way", it's about the oft-cited the factoid "90% of people are haptic learners, 30% are visual learners, 15% are auditory learners, 25% are text-based learners". Somebody did an experiment and found out 90% of subjects remembered something later when they had to learn to do it, but only 25% remembered when they had to read it. (All numbers made up, does not matter in the context of this comment)

Of course, this completely misrepresents the experiment! After learning to do something, you are 90% likely to retain it for a certain duration, after you read about it, you are only 25% likely to retain it, so in aggregate you only retain 25% of what you read.

The idea was never to find people who are "visual learning type" or the "non-learning-by-doing type".

That's what became of this idea in education through the game of telephone that mangles experimental results on their way from developmental psychology and cognitive science into education departments, and then into future high school teachers during undergrad lectures. Even my own high school teachers in Germany talked about learning types as if there was such a thing.