A much better situation would be to increase the speed limit where the road is good enough for that. That way, you are not getting annoyed that you are limited to 65mph on a straight road, and yes, while it increases reaction time it also makes you more focused on the road. I live in a country where the legal speed on motorways is 90mph, and frequently drive through Germany where I regularly go 120-130mph for long stretches of the Autobahn. And from my own experience(YMMV) driving 90-100mph makes you very aware of road waaaay ahead of you, a thought of looking anywhere else(phone, radio) but the road does not even cross my mind,because of how fast I am going and how much more intense of an experience that is. And then when I drive in the UK where the speed limit is only 70mph long drives get incredibly tiring and it's hard to remain focused, I have to stop regularly. Obviously, each system has its advantages and disadvantages, but none of them is ideal.

I'm not concerned about you or I, but the woman who just barely passed her drivers test on the third try and is trying to corral 2 kids in the back seat, drink her mocha frapuchino, and talk to her sister on the phone.

There is also the fact that the unrestricted portions of the German Autobahn were designed deliberately to accommodate 80mph traffic, unlike much of the urban US interstate system.

Of the 11-12 figure transportation projects the US could undertake in 2013, making it easier for people to achieve dramatically lower fuel efficiency by driving 10-20mph faster seems like a poor investment.

But that woman should not be driving in the first place. So if your training/testing system allows irresponsible people like that to get behind the wheel, then that's where the problem is,and not with the speeds on freeways. Most EU countries have massive fines for eating/drinking/talking on the phone while driving so most people don't do it - that's one problem solved.

This is a kind of "New True Scotsman" argument where, presumably, any example of an unsafe driving situation will be countered with with some failure of driver certification. Be specific. How many people do you think we should try to get off the road, in order to increase the speed limit (implicitly, by not enforcing the one we have now)? How should we select those people?

By looking at how other countries do it. In Germany you actually have to drive on the motorway at high speeds as part of your training . I have a friend who was told to drive at 120mph during his training, and the instructors argument was "the road is empty, the weather conditions are appropriate, and there is no speed limit on this stretch of the road,so you should know how to handle the car at those speeds". Yet in my own country I know people who have never driver faster than 40mph during their training, yet the legal motorway speed is 90mph. Are they ready for driving at those speeds? No, they are not.

And the argument "what about woman driving while talking on the phone, eating and tending to children??" is completely pointless, just like "what about drunk people driving??" - both of these groups of people should be banned from driving, as both pose a danger to safety on the road.

Sounds great. Tell me again how we ban the kinds of drivers who are likely to talk on the phone, eat, and tend to their children?

We don't ban them when they are likely, we ban them when we catch them doing it. Psychological tests complimenting the practical driving test would also be a good idea.

I'd argue in my case I should in fact be driving 80 mph a lot of the time, because everyone else is, and it is safer to go with the flow of traffic than it is to follow the letter of the law. As I'm sure you're aware, non-head-on collisions become more dangerous when the delta between speeds of the colliding objects are divergent more so than they are impacted by absolute ground speed of the colliding objects. In fact, even the DMV tells you to disregard the speed limit if it is at odds with the natural flow of traffic speed.

FWIW, I only ever drive 80 mph in 65 mph zones on large 5+-ish lane freeways. On non-freeway roads, I don't speed.

Though speed limits on most roads were set long ago, improvements in automotive suspension, steering, and brake technology in the intervening decades have raised the effective safe design speed of many highways. Eg. a 1970 highway with cuts, fills and curves spec'd for a design speed of 75mph is easily and safely navigable at far higher speeds today, even in comparatively low-end vehicles. This fact is very rarely noted in legal circles.