How would reversing the direction of a course affect certification?

I'd tend to agree with Scott. If the certified course is uphill, the reversed course would be downhill. However, the question of records would be easily resolved. I don't see a need for a new certificate.

Actually, after I sent the note to Scott, I realized that what the race director wants to do isn't clear to me yet (I'm the measurer). Rather than completely reversing the course, I think he just wants to switch the start and finish.

The course starts at point A on "Main" street and heads west. At the end it returns on Main street heading east and finishing at point B. The only thing he wants to change about the course is making the start at point B and the finish at point A. Points A and B are about 200 feet apart.

In this case would a new certificate be needed? It seems to me that anything a race director wanted to do that didn't require measuring anything, and resulted in a course of exactly the same distance, shouldn't require a new certificate. Examples would be this case, reversing the direction, changing the order of the loops in a 2-loop course, etc.

This is slightly more complicated than originally stated. One can conjure up all sorts of similar cases where the original route is duplicated by pieces of the changed route. I'd now be inclined toward a new certificate and map.