This is what's called "dumb working". Dumb because your productivity will drop permanently more than 60% if you do it for prolonged periods of time.
And if you, somehow, can't measure the drop in your productivity and it seems that you're at the same level of productivity no matter if you're rested and relaxed as opposed to stressed out, overworked, sleep-deprived and on the brink of burnout, then you're not doing actual work. You're doing make-believe work, like sitting trough endless meetings and nodding your head.
Somehow a lot of smart people seem to think that bruteforcing your way trough a problem (despite solid statistical data of this not working) is a good thing to do. But let's suppose that even if you could achieve the imaginary boost in productivity (2.5x or whatever) for prolonged periods of time (which you can't), most of the time this will not solve your problem. Performance increases below a factor of 10x are not very juicy targets. No matter how good you are, you will not be able to cram 400 hours in a week, because a week only has 168 hours. The way to solve problems that are that hard that you'd need 10x the amount of time to solve them, is to work much, much smarter, so you can get to grips with the problem.
Working smarter can make it possible to attack a 10x as hard problem, whereas scaling up work hours even if it'd work does not.