It actually made a lot of sense in my mind... just nobody took on the idea! Because wheel size is done on outside diameter, as with Mods using a 19" rim to give a fat rear tyre with larger air volume so a 25" rim could allow a bigger air volume tyre while keeping the OD 26". If a couple of tyre/rim manufacturers had taken it on for downhilling or whatever it could've been more mainstream I reckon. Nevermind!
No longer produced, but were available for a good few years.