The tribute to David Coleman the other week showed how you can be a great TV commentator without having to talk non-stop. Many only remember Coleman in his dotage but it is worth checking out on the iPlayer if you get a chance.
I'm not a fan of Tyldesley but Sam Matterface was dreadful when he was doing some of the Europa cup games on ITV4. Very dull voice, didn't make any attempt to make the game seem exciting and just didn't seem interested.