Or to put it another way... That's complete bull!
Grip has NOTHING to do with swing, feel, groove or whatever you call it.
I've also tried trad. grip and other than the fact that it's just not for me, the only thing I noticed was that it was a bit easier to play more quietly. Not to say that I couldn't play softly with a matched grip, but it was more work than with trad. grip.
One the rare occasion where I need to be whisper quiet, I WILL use trad. grip, so long as I don't need much in the way of fancy snare chops. I just can't get much speed with trad. grip (I know, practice it more).
All that said, there is something magical about watching Buddy Rich and those incredible snare chops he had... and all with trad. grip!!