I did run yesterday, and learned a new skill. My start time was 5:15 pm at a gnarly set of trails in Barton Preserve. Clearly, I needed light, and this was the time to learn to use my headlamp.
Trailrunning in daylight is fierce. Roots, rocks, snakes, coyotes, general physical ailments, and mental woes are enough on any given day. Now turn the lights off.
Add one spotlight in the middle of your forehead. I tripped and stumbled my way through almost five miles. I was very surprised at the one-meter memory my feet had, between the spotlight and the execution of action. There's a bit of darkness between the illuminated area and where your feet actually are, so you have to remember the patterns of the terrain and a split second later, follow through accordingly. At running speed, I had to trust that my body understood how to manage the delay. I never actually fell down.
Stop thinking and just do it.