Seems like an unhealthy attitude to me. I really dislike the perspective that education is at its best when the learning is most difficult. The best teachers are the ones that make things as clear and digestible as possible. Bad teachers are the ones that want to see you sweat.
It's not fundamentally different from athletics. If you want to be a good athlete, you're going to have to work your tail off. If you want to be an incredible engineer like Kelly Johnson, that ain't going to happen if you party through school. Nor would you have any chance of working with an engineer like him.
So ask yourself - do you want to design rocket engines? or cup holders?
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BTW, as for health, I came out of Caltech a far more confident person than when I entered. I knew what I could do, and was happy about it.
Now, I'm not arguing that hard work has no merit. Clearly, working hard can increase your rate of knowledge-consumption and get you further faster. For some people, you included it seems, that works out great. For others, the ever-present "110% or bust!" attitude can have serious mental consequences. Accepting that education can happen without rigor won't harm those that intend to push themselves anyway, but it sure would benefit the constantly stressed-out students.
No pain, no gain. You're simply not going to become an expert in any field, mental or physical, without a lot of hard work.