I think working hours is just a symptom. Look at the funnel... Korean kids spend an ungodly amount of time in class and doing test prep. Putting a cosmetic limit to the amount of hours worked doesn't change society on it's own.
Yet, South Korea ranks high for a First-World-Country in "increase in happiness".
If one sorts "World Happiness Report" according to "change in happiness 2005-2007", the top countries are mostly from the second- or third-world with the exception of South Korea.
