Is there a reason to drive 10 miles per hour under the limit?

Your question seems to imply that drivers must travel at the speed limit, which is false. The speed limit is a limit, not a required speed.

I absolutely agree with the 'not raised here'
but.. oh hell.. hahahahahahahha

but I laughed my ass off because I have seen those exact people around town too.
Sometimes so short they look like they are sitting on a phone book.

I just figure that the powers that be have determined the optimum speed for optimum conditions and that the safest thing to do is follow them.

People my think they are saving lives by forcing traffic to move slower than the speed limit, but they are actually increasing the risk for all. There will always be one person that is late or a chronic hotrod that will take risks in passing slow moving traffic that they otherwise would not. Then there is the increased risk of a pile-up. I HATE being in a string of cars on a 2 lane, because your safety is 100% in the hands of every (bored texting) driver in front of you.

If you're so impaired or unhurried that you need 10 miles below the speed limit, pull off once in a while. If you're trying to make a point, you are actually causing additional, needless risk. Then YOU'RE the guy that drives 10 miles under the limit and puts it to the floor when I try to pass!

Had a class mate who's parents drove 80 km/h when the limit were 100 km/h, think it was a mix of saving fuel money and be overly secure not driving too fast and cause a terrible collision.
..in short ..overly paranoid parents.

Ready cause of road rage, I believe.

I got hit with a couple of speeding tickets last summer, now I tend to be very cautious if I get on a road and am not sure what the posted limit is.

Course, some people just drive really slow, especially some of the very elderly drunks around my neighborhood (it's the upper midwest, and, like Willie Nelson said, there's more old drunks than there are old doctors...).

I generally drive 5 or 10 miles per hour above the speed limit, except in one circumstance. I like to have space when I am driving, and I hate it when idiots think they need to come right up on my tail. Space between cars is far more important for safety, there is no reason for fools to think they can get just a few feet from me when we are both going 60 mph.

I have an inverse three second rule. If the car behind me gets too close, I will slow down to the point that it is safe.

Elderly drunk drivers are the worst! They tip their bartenders with rolls of pennies. They get drunk at early bird specials. They're extra grumpy when pulled over by police. They go on and on about their cute and special grandkids when they're trying to set the paramedic who shows up at the inevitable accident to hook up on a date with their single daughter. Etc!!

I suspect that that answer is more than theory.

Drunk elderly man: In my day ... the police wouldn't hesitate to beat me senseless with his night stick. Whataya?! Chicken? Communist? Gay?
Police officer: Sir? I just pulled you over because your left tail light seems to be broken. No need to get angry...

I hope you don't think I use the term "elderly drunk" in a pejorative sense. I hope to become one myself someday.

In all my length-of-california driving, I followed what you said, for the same reasons. Well, I wouldn't slow down so much as to aggravate the tailgater.

I'm more of a speed limit follower in the city, if only because there are more fools per mile.

I think I mentioned what I call "dawdlers" at some point, I haven't seen one in a while but over the course of about six months I saw a bunch of 'em. Young men, most black but not all, crappy cars, going SLOWLY. Like 40 in a 65-mph zone. You pass 'em and give 'em a "wtf" look and they look back like "yeah, I'm going way slow, you got a problem with that?"

If it wasn't for the aggression part the pot idea would make sense. Never quite figured out if being annoying was the whole point. Maybe they didn't have anywhere in particular to go.

Elderly drunk Asian drivers.

Jesus wept.

You have lofty goals PD. Can your kidneys handle the task at hand?

I have been training, I continue to train. Someday you may call me sensei.

One advantage to driving slower than the speed limit is to provide more reaction time to adverse road conditions.

A tap or two on the brake usually gives them cause to back off in my experience. They certainly know from experience that if they rear-end you, it's their fault. You'll make it a heck of lot less fun when they realize they are going to have to watch you 100% of the time in order to mess with you. I usually tap the first time and if the message is lost, a little bit of a bump the second time. I don't want to mess with them, I just want them off my butt.

I believe you are right on 2 counts: no where in particular to go, and being annoying is satisfying in of itself for them.

rotfl