By the way, Mario 3 doesn’t really change the “jumping” rules, but rather the “walking off the edge of a platform” rules. In levels without slopes, you can inch your way over the edge of a platform and Mario won’t fall as long as even the slightest bit of his foot is on the edge. In levels with slopes, however, Mario will be allowed to fall as soon as his midpoint passes the edge of the platform. Without this change, he’d “hover” over the edge of every slope you’d try to have him walk down.
By the way, Mario 3 doesn’t really change the “jumping” rules, but rather the “walking off the edge of a platform” rules. In levels without slopes, you can inch your way over the edge of a platform and Mario won’t fall as long as even the slightest bit of his foot is on the edge. In levels with slopes, however, Mario will be allowed to fall as soon as his midpoint passes the edge of the platform. Without this change, he’d “hover” over the edge of every slope you’d try to have him walk down.
I am really humorously confused about why this comment got so many upvotes. Am I missing something?
(It’s a summary of the relevant bit of information taken from a very long blog post that was mostly about something else.)