@gone-troppo they will, probably, but I doubt it will ever make sense and cover all cases. Those algorithms are based on observation of the physiology of people running, but trail running has too much variability to ever reach a similar stability. You could be just running flat on a trail, running uphill on good trail, running on technical trails, pulling on chains on very technical terrain, and for the watch you’ll just be exhausted and running very slow. It is not just altitude gain, that’s way easy, is the variety of terrain that will never allow such algorithms to work.