Lunar scholars depend on intelligence not knowledge. Their capabilities are intuitive rather than deliberate. While their Abilities have little bearing on their potential (which is why they are not included in their Excellencies) what they learn from one situation they may not be able to apply to another, this is not of consequence to them since it's their underlying intelligence that's the font of their ideas, lacking Abilities is not a handicap to them. Only martial arts of all disciplines requires such refined training to learn.
   To put it simply Twilight skills are based on what they know. Moonshadow Caste skills are based on what they think. This did make them inferior to the Solars in terms of raw power but they focussed on a different area.
   Of course Twilights think too, their power comes from thinking about something and they're exceptional at it. The Moonshadows' power wasn't that they were the best in any field but that they can use their minds in any way they please. Luna didn't create her champions to compete with the Solars. She made them to do things the Solars couldn't.
   *Moonshadow is my name for the No Moon Caste.