@Woodrow and
@JMT if you really wanna learn to ride, get yourself a rigid single speed! You’ve got no choice then but to pick the best lines.
I built one a few years ago. It’s a fun change of pace. Very simple, and very quiet. No chain slapping. No suspension setting to worry about…only control you have is tire pressure. It takes about 1/2 a second to realize how spoiled you’ve become with your cushy 140mm trail bike and you hyper focus on line.
The other thing you’ll notice is that you will go WAY faster XC. The bikes are super light without the extra stuff (mine weighs in the neighborhood of 20 lbs) . And…uphill, you gotta pedal! Stand up or sit down, that bike ain’t getting to the top unless you pedal. You’ll typically go MUCH faster than all the geared bikes up hill.
When you get back on the Cush bike, all that line selection stuff stays with you, so it will typically make you faster there as well.