It mattered when I was struggling to get back into shape a couple of years ago. Back then 400 yards of a 1%-2% grade would induce an asthma attack and I'd have to pull over and catch my breath. Wish I was kidding or exaggerating but nope.

So when I consulted various maps that only guesstimated the total slope at 0% for a stretch of a few miles, it was discombobulating to discover that 10 mile ride actually consisted of roller coasters with 50 yards of 11%, a plateau, another 400 yards of 3%, a 50 yard -2% downhill, etc.

Now I just regard those roller coasters as conditioning challenges for getting faster and stronger. But two years ago it felt like a life and death struggle and not fun at all. Especially on busy streets.

Even when a busy street in traffic is wide enough to be safe, and even if it includes a bike lane, it may not be suitable for cycling with folks who aren't in good shape. I've seen that often with folks who rent city bikes that weigh about 40 lbs, and end up walking uphill when they misjudged how steep some hills are from a cycling perspective. It ain't fun to be trapped in those poorly designed bike lanes with traffic to the left and a door zone to the right from curbside parking, while huffing and puffing uphill at 3 mph on a 40 lb city bike.

And that coincided with my dislike and distrust of Google maps, which can get you killed around here by relying on it for bike routes. That's when friends tipped me to cycling apps with routes that actual local cyclists rode, with accurate descriptions of segments to help me guesstimate whether I was fit enough to tackle 'em.