A flame that burns twice as bright burns only half as long.
By the title of this missive, you can guess the biases in my opinions here. Sleep seems to be a natural evolutionary necessity among most organisms. However, the way you sleep is definitely cladistic, in the sense that certain classes of evolutionarily related organism populations have distinct and similar patterns of sleep. Some organism populations sleep when it's dark. Some when it's light. Some may take only "power naps" or only rest.
Since I was a child, and I see this in my eight year old daughter also, sleep has been more of an hindrance than a necessity. Don't get me wrong: I love and appreciate a long great sleep extremely, as much as I love almost anything in life. I think humans do need their sleep. But our personality, and social and biological circumstances influence our sleep habits strongly and I believe that we can behaviourally manipulate our sleep regulation at will and don't have to adhere to standard conventions of how, why, and when we should all sleep. Given that we've colonised all regions of the planet, and given that there now "cities that never sleep", this has already become a reality of sorts.
During the course of human development, the need for sleep changes while biological changes occur that makes sleep much more difficult. For example, melatonin, a hormone derived from serotonin and a tryptamine (one that I know and love; a reference to people familiar with Alexander Shulgin and one of his books), generally regulates the sleep cycle in humans. The pineal gland that produces melatonin calcifies as you age, and thus produces less melatonin (I believe this is near universal for humans). Therefore much older people sleep less than babies, but I don't think this is because they need less sleep. They actually may need an equivalent amount, but are unable to sleep as much due to the pineal gland calcification. Thus the proliferation of available prescription and nonprescription sleeping remedies, all of which are not perfect for humans in general.
But aside from the biological issues, before there is serious pineal calcification as you age, there is no doubt that as a human, as you sleep less, your productivity, efficiency, and cognitive ability decreases. For some, this decrease in efficiency is a cost/benefit ratio and worth it. I certainly can go one night with zero sleep with a barely noticeable change in these areas. However, there is a great increase in efficiency due to being in the "zone" of productivity that a good night of sleep will almost certainly ruin. It's much more efficient to put in the extra few hours and finish up a particular task (from writing a program to writing a song) and "catch up" on sleep later.
If I continue this lack of sleep for more than one night, even with power naps of 2-4 hours, the difference becomes noticeable but I still remain highly functional for most activities. I can continue most of my adventuring (climbing a mountain in one shot without sleep is one of my favourites), I can mostly do science, work on music, and can definitely work on most human bureaucratic activities. For the record, the maximum I've gone without any sleep, not even a slight nap, is about 100 hours and that was last done at age 19; I also repeated it in a similar style at age 32 and age 35 (actually as I write this).
So I prefer to lead a life style where I sleep little and get a lot done and then catch up on the sleep later. This not only subjectively makes me happy but also is more productively efficient compared to leading a regular schedule (which I've also tried for several months and I've realised is not for me). Almost everyone I've spoken to who lives in this manner says that the lack of sleep eventually catches up and you end up taking a big long sleep, though it's not a linear catchup, which works in the favour of the nonsleepers. Bill Gates apparently once said that he needs less than four hours of sleep a night, and while I have no respect for Microsoft, I can't say he's not productive.
So what this mean in terms of the big picture: does a person who sleep less have more of a survival advantage? One may think so both socially and biologically. As a professor who does cutting edge research which needs high levels of productivity, I've certainly noticed this in my own students. In general the idea of computer geeks going on for long stretches without sleep is anecdotally well established. Also, some of my adventures are not accomplishable without my current sleep habits, and in some cases, a need for sleep (or the training of living without sleep), may have well saved my life. People who need less sleep simply seem to have higher energy levels than normal and this I think is beneficial in all respects. This is exemplified by my some of my children who seem to have acquired these abilities over time (my wife also has similar sleeping styles), though I am not claiming that this ability to function for days without sleep is a genetically inherited trait.
However, lack of sleep has been associated with a host of behavioural and physical problems and I think there is a trade off point for everyone. In my own case, my epilepsy may be related to my lack of sleep though not all my doctors and neurologists concur. As I say above, getting things done as you need to may reduce stress, and even save your life, but it can also add to stress when you've crossed your own threshold of sleep and productivity (i.e., frustration caused by mistakes). Recognising the latter is a good ability and that's what usually at least causes me to have a nap.
So the balance of what you can do is a factor of what you wish to accomplish in life and your personality. One question is whether longevity of life is relevant to you. I myself would give up a few (or even several) years off of my life for the productivity I've already gained from my sleeping habits (and I address some of this my Death missive). On the other hand, controlling melatonin production may be a way to ensure longevity. I however do believe that with appropriate training you can acquire the ability needed to manipulate sleep to your optimal advantage.
There is a distinction between hard and smart work, which I've not made here. By the latter, I mean being so lazy you do the least to get the job done so well you never have to tweak it again (i.e., being extremely optimal or efficient). The missive is written with the assumption that you're living your life (or working) smartly, even with less sleep than "normal".