Your right about the Tandems- Till they go uphill. But We have a system if we don't want to get wheelsuckers. It is easy to do 25mph on the flat wirh a Tandem by just turning the pedals. Couple of turns of the pedals and we can be doing 30. So if we can feel that we are towing "Too" many- we just accelerate and wait till every one catches us- then slow down again. If anyone hits us- they will come off worse. Even experienced wheelsuckers don't like the accordian in a line.