If you're first eye was non dominant and ended up being reading doesn't that mean your dominant one is the distance one?Not sure about the dominant eye statement. My first eye which accidently turned out to favour close vision was my non dominant eye. This means my dominant eye is now my reading eye. I have no problems now with distance or reading. In fact I can see distance or close up better with both eyes than I can with either one.
I understand that not everyone takes well to monovision. When my wife asked for it the surgeon insisted that she had a month using monovision contact lenses. She hated the lenses but had no problem with monvision and went ahead. Great, no more specs for her either.
Your point about cateract surgery being predictable, my first eye was miles off. When I used the word "mistake" to the eye surgeon who measured my eye he said that it was "not an exact science"