What this statement suggests is that Buzz has never really understood how to tune a guitar properly. In common with many guitarists who don’t understand the nature of harmony, where it comes from and how we perceive it, Buzz had been attempting to tune his guitar so that all individual chords sound correct only to discover that this distorts the intervals comprising other chord shapes, a simple error but one that is very common in guitarists with no formal musical education but who nevertheless have a sensitive ear for harmony. Such mistakes stem from a lack of awareness that the only way of achieving consonance on the guitar is to tune it so that each individual note at all points on the fingerboard are the same or octave multiples of each other.
A method of doing this, published by the Guild of American Luthiers can be found here: Guild of American Luthiers tuning protocol
“You play one chord shape, like A, and it plays in tune, but when you play another chord shape, like D, it's not quite in tune; close interval chords often sound wildly out-of-tune; and no matter how carefully you tune your guitar, some chords still sound only slightly better than fingernails on a chalkboard”
