Correct, I had forgotten that caveat. This D34/D50 discount was one that had fallen off the radar so to speak. Most passengers eligible in Scotland either got free travel (visually impaired) or were using a disabled person's railcard and/or travelling at a time where the full off peak fare undercut the discounted anytime fare. Therefore it became very rare to issue one.
However, the fact that the anytime & off peak fares are the same* means that for day returns the D50 discount is often the best - for those remaining in their wheelchairs. Visually impaired passengers, of course getting free travel (in some cases with a companion).
*the introduction of the £10 minimum fare by, we suspect increasing those anytime fares currently below £10 to £10, may, once again, change the dynamic. But we digress.