Therefore, if an employee needs ten hours of sleep to operate at maximum productivity the next day, they should have that ten hours. Everyone knows that there are twenty-four hours in a day, so those ten hours off leaves fourteen hours.
Among that fourteen hours, an average of a maximum of two hours is spent commuting (one hour to the job, one hour back, using London's non rush-hour statistics - http://www.itv.com/news/london/2013-05-21/londoners-endure-longest-commuting-times-in-uk/). That leaves twelve possible hours of productivity.
In those twelve hours, one has to have lunch, breakfast and dinner. Each might take an hour, including time for preparation and consumption. That takes three hours out of each day - nine remaining.
Now, here's the kicker: An average job is 9-5, yes? That's eight hours long. That leaves one hour of free time and relaxation, which may be spent at home watching the latest Doctor Who or re-runs of Breaking Bad. Alas, that is the length of one episode. If you consider that time flies when you're watching a film or TV episode, consider that in a working context, day in and day out! This is literally working your life away, especially if the 9-5 increases in length.
So what happens when a 9-5 increases to... let's say, 8-5? Why would one do this? Maybe to beat rush hour - BUT ONLY IN THE MORNING. Maybe to increase productivity and reduce the possibility of the workers being stuck in traffic, and overall trying to aim for having the workers in one place. Generally, to iron out the kicks, hourly speaking.
But that leaves no free time in the day at all. Except for whatever spare minutes you have when commuting, whatever time you have left when not needing those ten hours of sleep (some can get by on as little as four, but hardly anyone can - and having too little sleep in too many days in a row can basically cause you to pass out. Lack of sleep can also cause further side effects, such as depression and forgetfulness - http://www.webmd.com/sleep-disorders/excessive-sleepiness-10/10-results-sleep-loss) should be well-spent.
Additionally, the body click also judges best when to go to sleep. (http://sleepfoundation.org/sleep-topics/sleep-drive-and-your-body-clock) As demonstrated by the article, adolescents and older typically find it hard to fall asleep before 11pm.
What's 10 hours after 11pm?
That's right - 9am.
Therefore, it is my assumption and conclusion that when the working hours are increased in the morning for purposes such as beating rush hour, this is to the detriment of the workers, and their health - and potentially, any company employing this scheme in order to increase productivity. This is because as our natural body clock dictates how much sleep we need and when, it is very hard to adjust to an early start. Also, by not extending or reducing the working hours after the afternoon rush hour to avoid the traffic at that time, this suggests a lack of empathy for a worker's afternoon situation in getting home.
Therefore, rather than allowing them to go home a mere fifteen minutes early or late, it would be best if they went home at seven, thereby avoiding the traffic almost entirely. In compensation for this, the morning rush hour should also be avoided, and the working day adjusted accordingly, for a eleven am start. This would allow for a multiple-whammy of allowing the workers to get enough sleep (11pm to 9am), enough food preparation/waking up time (9am to 10am) and commute time (10am to 11am). And on top of this, if the workers went home at seven, they'd be able to travel quickly without (many?) holdups (7pm to 8pm), enjoy the evening entertainment (8pm to 11pm) and go to bed (11pm to 9am).