I'm positive Ed would say to not run lower octane than you were tuned for.It's pretty common to use a little more conservative tune for a track car than a daily driver. I'm not sure what the controversy is.
And also love to hear Ed's thoughts on whether it's OK to run 91 octane with his 93 Oct tunes. Or any actual tuner for matter. I've yet to meet a tuner that gives the ok to run 91 Oct on a 93 Oct tune, as the other poster is proposing.