The science behind eggs. When they are laid eggs have a coating to protect them, because the shells are porous. The coating works to keep air and bacteria out of the egg. In the USA this coating is washed away before sale. If this coating is not washed off you can safely keep eggs on the counter. Under the shell is that membrane which also protects the eggs. In a fresh egg that membrane is closely glued to the shell. As the egg ages air seeps in and loosens the membrane. This happens faster if the eggs are washed. Most of your handy hints will work for washed older eggs, but very little will work for fresh eggs. The best hint is to use older eggs. And if they are from a farm or the backyard they need to be washed or kept longer.