Wow, when I moved to Mexico, I could not back a car down a street. I could back up a little to parallel park, but not down a whole street. Now I can.
The first time it happened that I HAD to, I had turned on a dirt road to go to a friend's house - about eight years ago, and on the other side of the rise the road ended and it went straight down into a ravine. This was within the city limits of San Miguel! OMG, I freaked. I started backing up at about 1 MPH. There were deep ditches on both sides and a little tiny bridge just to add to the fun of it all.
I was a wreck when I pulled back onto the highway and went another way. I needed a drink when I got to my friend's house a longer way. But heck, now I can back up just like the taxicab drivers who take GREAT pleasure in backing up a block or two, at 20 mph.
I was reminded of this story this morning when I saw a van with Washington State plates on it going down Cuesta de San Jose where it had become one way and they were going the wrong way. There was a giant Coca-Cola truck and other trucks coming up the hill. I walked up to the driver and passenger, which were young gringoes and said "You'll have to back up the hill". The look of panic on both their faces reminded me of what I must have looked like lo those many back-ups ago.