At home I use only a fork even when cutting steak unless its real tough. Some people I know use a fork and knife for just about everything but my family exchanges glances at this. I don't know many people who use the knife as a loading utensil, this is amusing to me.
At school I use proper etiquette and never cut things with the side of my fork, I use all proper utensils including desert and dinner forks and spoons. (unless of course I'm eating alone or only with a few friends )
Most often though, in both situations, I am eating with chopsticks which I find easier.
I think that today you just use your dominant hand, right or left, but I always heard that the reason the right hand was used in some cultures is because the left was a wiping utensil of sorts(ewww). I don't think the tradition is well known today.

-Ha! We used to do utensil of the day in high school also!-