My argument for requiring only a single ride for re-certifications of expired courses was based on the fact that the second ride serves no purpose in this case. You are already requiring the first ride to closely match (within 0.08%) the ride that someone else did of the course long ago.
But if you change the requirement of that one ride to be that it only has to confirm the course is at least as long as advertised, then my argument no longer stands. Someone who does a very poor ride of the course will always confirm the course is at least as long as advertised, even if it is a bit short!!
If we are going to allow a single ride to re-certify a course with the at-least-as-long requirement, we need to be very careful about who we allow to do that single ride.