"One of the problems of having a direct harmonic sense is that it's very difficult in general for me to teach my spells to anyone. Fast-flight is one of the ones I haven't managed to translate. I might be able to translate a stripped-down version with fewer conveniences, but so far no one has expressed serious interest in being able to fly very rapidly while making a terrible racket that can be heard for miles in every direction, leaving behind a very obvious trail of disturbed air, and running out of breathable air in somewhere between one and six hours. Or about a minute if the spell didn't include an air bubble at all."