In reply to alanlgm:
Was the top-rope running through the same lower-off as you were planning to use or was it adjacent? If the former what were you planning to do at the top? As mentioned above, having one loaded and one non-loaded rope running through the same lower-off is a fundamentally bad idea.
Walls tend to be a bit reluctant to let you pull down
in-situ top-ropes. From experience, despite promises to put back as found, often this task gets forgotten about, done poorly (gates not closed at top), or done dangerously (top-rope used as lead-rope or both ropes put through lower-off).
Perhaps this helps explain why most supervised commercial walls would prefer routes to be defined as either "lead" or "top-rope" and boundaries not blurred.