On Wed, Aug 26, 2009 at 1:59 PM , Greg Potts wrote:

> Hi Marc,
>
> The benefit of "drafting" is the reduction in relative wind speed
> lessens the load on the engine.
>
Surely the poster who said he just settled in behind a semi on hills
wasn't talking about the practice of "drafting" (following very closely
behind another vehicle so as to avoid air resistance).  Of course,
because the vehicle ahead might make unexpected maneuvers, this is
extremely dangerous.  I think the poster simply meant that he follows
behind the semi at whatever the semi is running and at a prudent
distance.