Originally Posted by
RChung
That's a different problem. Are you saying that if I hold my hand above a table top, there is no "right" distance between my hand and the table top? You can't measure a distance between two points unless they're connected? How about distance in the vacuum of space? In fact, the meter is defined as 1/299792458 of the distance light travels in a vacuum in one second, so we can certainly measure a distance in a vacuum.
There is a distance, and there is a measurement of that distance.
If I walk up the 8 foot hill in my yard, did I not climb any distance? That section of my yard is between the 350' and 360' foot contour line. The map data doesn't have the elevation data for every square inch of ground. If I mow my grass in then I'm climbing and descending multiple times that 8' of height, but I won't get any credit for climbing going by map data.
As another has said, with barometric sensors, resolution is the issue. Both for the devices ability to sense a certain amount of change reliably and factors that cause noise, unreliable data that have to be taken into account. If I go up and down five feet is that climbing and descending? If I go up and down 1 foot is that climbing and descending?
Getting back to the topo maps, it's possible to ride between the contour lines in places for many miles. That doesn't mean no climbing or descending was taking place unless your resolution has to be 10 feet or more.