And how do you make sure these super-productive adults with their optimized workflows are, you know, actually working on the right thing?

It's easy to naysay "all that traditional biz school bullshit" until it's your job to make 10 top-notch programmers who are each convinced they are great architects to all write code that somebody else is going to pay for.

Fundamentally I don't think you can motivate people. We may actually be saying similar things, but I think you can only really demotivate them by treating them in a psychotic, demeaning or inhumane ways. Motivation on the other hand is is an emergent, instrinsic human quality that can only be killed, not created. "Not killing it" as you say is largely a question of people actually contributing to work that they find worthwhile and having their contributions respected by the company. But there are some folks who would never be motivated, as they simply do not have that quality within themselves.

There are classes for that in business school, such as orgazinational behaviour and leadership, but like most of academic learning, you learn to pass a test, not on how well its applied in the real world