Howdy,
I personally climb on the Schwabisch, finding that it's "bar" is in the perfect location for my right thumb to grip and loosen/tighten the knot, much like the Blakes is. In my experience this knot advances easier after loading than the Blakes hitch however. Sorry I don't have a camera handy but found a great article by Mark Adams on this topic, with good photos. Hope he doesn't mind my posting this link:
http://www.????????.com/pdf/climbing_hitches.pdf