I'll offer a reward of coconut cream pie from Big-O's (see other posts) to the person who can get a Schwalbe Marathon Plus either on or off without a tire lever. Make that three tire levers.

".........you're a better man than I am Gunga Din"

If I need it, I have no problem using a tire lever for the last little bit of tire to clear the rim. Just be careful not to pinch the tube.