There are lots of ways to teach effectively. Not every student responds well to every teacher.
I can see how some may not enjoy learning from Boon. That doesn't mean that WHAT Boon teaches is wrong, just how he presents it may rub some people the wrong way. Others thrive in the same environment.
Boon is very straightforward. If he sees you do good work, he tells you it is good work. If he sees sloppy work, he tells you it is sloppy work, and makes you redo it.
If being treated in this manner offends you, don't go.
My take is that yes, you can let the student try stuff, and make mistakes, and suggest alternate methods, etc., but that would take longer. I mean, doing the "softer, kinder method" that kakejiku suggested. There's merit in that approach. But, we're working with trees here, and if a student messes one up, well, it's not the same as ruining a piece of paper, or stick of wood that can be easily replaced. And there's the matter of time. There's so much to learn, so little time. Boon is trying to convey as much information as possible in the fastest way possible that the student is able to absorb. It IS much like trying to drink from the end of the firehose. I know I miss much of what Boon is teaching the first time I hear it. Which is why we do each class three times. I hear (and learn) something new each time.