De facto speed
"What if I told you, that the distance Mario moves, isn´t necessarily equal to his speed "
Surprised? Well, it´s true.
Mario´s speed only indicates the speed he would be travelling on a flat ground, but when Mario moves on slopes, even though a speed meter measured his speed as high speed, he would move slower.
This real speed is called De Facto Speed, and it varies with the steepness of the slope, but it doesn´t matter if he is moving uphill, downhill or sideways on the hill.