I met more people on the trail on Monday's ride than on Thursday's, yet it felt far less crowded, because everyone out there on Monday observed the accepted trail etiquette: bikers yield to everyone, and downhill riders yield to uphill riders. (Doubt me? See IMBA'a Rules of the Trail and CA State Parks doc on Mountain Bike Rules.)
Huge kudos go to a runner and a hiker I passed on my way down Space Mountain. The runner was coming up, and I pulled over to let him go by. He warned me that there was a hiker a little bit behind him. When I spotted the hiker, she was headed away from me down the trail, so she couldn't see me. But she had her headphones off, so she could hear me call out a friendly "Hello." As I passed, I thanked her for keeping her ears open, and she remarked that with all the bikers on the trail, it just seemed smart.
It's amazing how easy it becomes to share the trails when everyone does their part.