I've never had them split open unless I wanted them to split open, ie over cooked them. You can cook them to aldente or cook them to mush depending on what you are doing. You do not need to cook anything in salt water ever, though the older generation apparently cooked everything that way.
My pot of beans which I have in the fridge at all times is there for 5 to 7 days, depending on the bean. Black beans seem to last forever.
Oh and LOL on the complete protein debunking, I was raised on that one. It was like one of the ten commandments in my house.