Late stay = Hard work?

I've always been asking this question to friends about late stay and hard work. Because I've always been confused about my stand on this. Considering today's work culture especially in the IT industry, late stay has become a norm. People don't mind spending 10-16 hours in office. So does this equate to productive hours?

Maybe in other industries like those involving manual labor, working more may equate to working hard because more output will be obtained. But the IT industry works differently (by IT I mainly refer to software producing companies). Here people work their best in bursts because the main tool used is the mind and concentrating cannot be done for long stretches of time. No person can be productive continuously for 10 hours. It is in taking breaks and then concentrating for some time which produces the maximum productivity. So we have different views regarding late staying. One is that because we work in bursts, late stay is good as we can relax and work periodically instead of working under stress. This sounds good but then what happens is people tend to over stress themselves. That is why many young people are suffering from illnesses like blood pressure, diabetes, heart problems, which sometime back were heard of only in old people.

Looks like it is the managers who promote late staying. They themselves stay late and expect other's to do so too. Now working late during deadlines is acceptable but when it turns into a routine something is wrong somewhere. It seems that the crazy scheduling of work is where the problems start. Companies are into competition and the best place where they can compete is reduction in the delivery time. But this decision is paid heavily by the employees in terms of mismanagement of time.

So what is the solution? Frankly, I'm still searching for answers by analyzing what people have to say about this. But the solutions are definitely there. Many countries like Germany, UK, etc have strict norms laid out when it comes to work. Do you work with utmost efficiency and go and live your life. Such norms should be enforced by the organizations like NASSCOM who have a say in the IT industry. Only then can we expect some regulation in this matter.