[gaurav_v]

I broadly agree with you, but I think the issue is more subtle. Ambitious people will always work very hard; the danger of working hard is that it necessitates a degree of path-dependent myopia that can lead one to miss huge opportunities.

The most ambitious people are quite concerned about this, and try to use leisure as a comparative advantage. The article is pretty fair in painting this portrait: the author admits that the scientists construct their lives around their work (Darwin worried about getting married, for instance), but points out that constructing their lives around their work involves the construction of leisure.