"Too harmonious?"

Is that possible, Herr Kappellmeister? can music be too harmonious?

In this feature on an a capella group in Vegas called Mosaic, a phrase jumped out at me:

The band also offered a very Vegas sense of pacing and a suitably pretentious theme: vocal music through the ages. It opened with a far too harmonious Gregorian chant and ended with an encore of "Wonderful World," coming after covers of Sly and the Family Stone hits, Kelly Clarkson's "Breakaway" and perhaps, most impressively, Dave Brubeck's "Take Five," complete with vocal bass and drum solos.

They sound interesting, but I'm not sure what the writer meant, perhaps over-produced? or jazzy, with too many ninths? or slick and saccharine like Disney's same-approach-to-every-style-and-era arrangements?

I'd like to think a music journalist was knowledgeable enough to have meant "too harmonious" as in "harmonized. Period."

How many of you have choir- or parish-members who insist on trying to add major and minor thirds to even the simple chant Paschal "alleluia"?

Ghghghghghghghg! (that's the onomatopoetic of my teeth being set on edge....)