I would guess Larson wasn't a fan, and thought that "new age" practices were mainly performative and non-productive, leading practitioners to get stuck in repetitive little circles, getting nothing done in the end.
If so, it's a pretty cynical take IMO, and certainly one of his more personal, brassy ones.
I too don't know what this means. After much searching I believe this could be a reference to the whirling dervishes of Sufism. More likely than dowsing in my opinion.