Ken, the coping sled was pioneered by Bob and Rick Rosendahl of the Router Workshop. Many companies have jumped on the band wagon with copies of the original sold by Oak Park as well as copies of their box joint jigs and the EZ Link System. The coping sled is one part of the Raised Panel System which is not available at this time. You will find several episodes of the show featuring this system being used to create raised panel doors quick and easy. The fence on the sled should be flush to your table fence and acts as a backer board to prevent tear out. It also acts as a quick set up guide for your bit.
"Living in the D" (this means Detroit!)
"It's fine to disagree with other members as long as you respect their opinions"