The advert is, of course, appalling. There needs to be space in life to be not working, so I hope the advert is more of a joke that a serious suggestion as to how a company might work.

But the idea that every time someone spends more than maybe 40 to 50 hours in a week working their productivity drops by more than enough to negate the usefulness of the extra hours is pure nonsense. Long periods of crunch mode working have been known to be counterproductive rubbish for a century or more (pity we can't get more managers educated about that) but short periods can be very effective. I know from personal experience that I'm not productive when I'm too tired to think straight, but I also know from personal experience that doing 66 hours a week for two weeks isn't enough to put me into that unproductive state, although doing it for 3 weeks might be. I also found that when I was too far from home to spend time with my wife and kids I could work long hours without getting too tired to be efficient provided I knew that when I was back within reach of home I could take the time back. Having short overworked periods every now and again, provided they are matched by underworked periods every now and again, is not harmful unless the periods get too long.

So yes, there is a problem (patrticularly in computing - not just in software development, it happens in hardware development too) that there can be crazy overcommitment for which incompetent managers (perhaps the majority, sad to say) attempt to compensate by having eveyone work silly amounts of time for periods long enough to be counterproductive. The answer isn't to prevent people working 60 hours in a week evey now and again, expecially if they can get a couple of extra days off work or a couple of weeks with only 30 hours in compensation, and even - provide it's sufficiently rare - if the only exchange they get is pay for extra hours. It is rather to educate managers so that they don't expect intense overtime to work for months when we all know it only works for a short push (say two weeks, or maybe three weeks if the extra hours are low enough); and of course to educate the junior programmers/engineers who in their early 20s think they can work effectively for three months on 3 hours (or less) per day of sleep so that they know they can't actually do that.