I have always felt that accurate splits were an intergral part of course certification. Agreed that the start to finish distance is almost always all that is certified but when the splits are obviously innacurate, the course distance is suspect to the runners trying to figure out just what pace they ran.
I was also recently re-certifying a course that was to be run backwards. Since it was a 5k with mile splits and the start line was being moved up to almost the old 3 mile mark, adjusting the splits became more of a question of keeping track of which way to move from the old marks. I chose to adjust rather than ride the entire course. Upon completion, I drove the course and noticed that I had adjusted the wrong way on two of three splits. Out came the dark spray paint, the bike, and new accurate but not certified splits were in place.
I could have gotten away with using the old splits, but my conscience dictated the extra effort to provide the runners with both a certified distance and reliably accurate splits.
Was it necessary? No, but I felt it appropriate.
Mike Wickiser