I have a 30" DL and use a D-loopand can shoot my buddy's 29" bow.

The best thing to do is try it out and make sure your anchor point is in the right place. Depending on the bow you should be able to either adjust right on the bow or buy modules to increase the DL.

Making sure the string anchors on your face properly is the most important thing. The arrow nock should be udner your eye.