I went skiing the other day far from my home. When I got there I realized that I had taken one of my boots and one of my wives boots. Luckily one right and one left. Unfortunately, she is a 6, I am an 11. Nonetheless I painfully put them both on, as a penance for being a bone head, and went up skiing.
It wasn't too bad but I had to adjust my binding to fit her boot and I could only Tele turn to one side on account of my scrunched toes. I have skied with my boots on the wrong feet once, during my hung over college days, when I thought it odd that my buckles were rubbing together like never before. I often ski with my skis seemingly on the wrong feet but this was a new extreme experience. The four hours of skiing were not bad but the two hours I spent waiting for a downloading tram in the après ski bars became excruciating, since I dared not take off my boots for fear of not getting them back on.
When I finally stumbled to my car and took off my boots, I expected to see bloody toes and black toenails but found that my foot did not look bad and it felt real happy to get out of that boot. By the next day my feet had completely recovered and I have determined that size really does not matter. For ski boots, that is.