"The typical American male devotes more than 1,600 hours a year to his car. He sits in it while it goes and while it stands idling. He parks it and searches for it. He earns the money to put down on it and to meet the monthly installments. He works to pay for petrol, tolls, insurance, taxes and tickets. He spends four of his sixteen waking hours on the road or gathering resources for it. And this figure does not take account of the time consumed by other activities dictated by transport: time spent in hospitals, traffic courts and garages: time spent watching automobile commercials or attending consumer education meetings to improve quality of the next buy. The model American puts in 1,600 hours to get 7,500 miles: less than five miles an hour." - Ivan Illich

 Groups that I lead (and I am humbled by the riders who've let me do so)
 *rarely* go more than 65 MPH in the straights. We exceed that speed when
 overtaking cages. Cornering speed is whatever each rider is comfortable
 with. *If* I lose the headlight of the rider behind me (this group is full
 capable riders more capable and/or experienced than myself, and sometimes
 I lead merely because I've planned the route, etc.), I slow down until I see
 it again (even if it means cruising the straights at 30 instead of 60),
 and expect/hope others in the group to do the same.

 The main reason I "manage" a group ride in this fashion is because I've
 been on local rides where "really fast guys" go ballistic and "run away" from
 you, which has always left me asking, "Are they really riding *with* me?"
 For me, personally, group riding is about *sharing* good/new roads with
 good/new friends, and that's gets tougher to do as average ride speed
 climbs higher and demands more of each rider's concentration. In other words, the
 more you're concentrating on not falling down the less you're
 concentrating on keeping it a genuine group experience.