This seems about as valid to me as those folks who proclaim "the only way to light a cigar is to use strips of cedar." I've lit cigars with matches, cedar strips, butane torch lighters, butane soft flame lighters, and soft flame fluid lighters (i.e. Zippo, Bic). And you know what? They all worked well enough and I could detect few, if any, flavor differences based on lighting method. The cigars I lit with cedar tasted just as good as the ones I lit with matches and butane torches. The only one I wouldn't use again was the soft flame fluid lighter, as it seemed to impart the flavor of lighter fluid into my cigar. But that aside, all are perfectly acceptable lighting methods.
Wetting a cigar down before smoking it just seems pointless, especially if the cigar has been stored in a properly maintained humidor. But you know, whatever floats your boat. If you want to smoke a wet cigar, go ahead. I just think the whole thing seems like more pointless gimmickry.