There's a bunch of new riders who have just joined the forum and are looking around for some rides. My guess is that not all of them would want to ride all the way from Blackburn to, say, Dunsop Bridge and back. Nor would they fancy doing it in the rain. The idea of leading bike rides (or walks or anything else outdoors) is to put aside your own ambitions and ego for the day and help others less experienced than you to enjoy the day without stress, which means waiting for the slower members of the group. By doing an out and back ride, anybody who doesn't fancy the full distance can easily turn round and head for home confident they won't get lost.