It's a starting point. Glad you're considering it. Have you noticed other similar concentrations of shootings incidents kind of along the same highway over six months anywhere else? If it is indeed random and different people, then similar patterns should repeat elsewhere? My guess is that it may be a group of 2 or 3 younger people playing a very dangerous game, who may have escalated as they went along. I get the sense that there is a driver, a shooter, and a spotter, and that they may take turns shooting. Their schedule may fit high school athletes, with a break for lunch. I hope I'm wrong in this speculation. The Denver shooting may have been to distance it from them, or as you suggest it could be various people, or just one very frustrated person and copy cats. Until it is known what really happened it makes sense to consider all incidents that have a potential to be related.