You don't need 'qualifications' but you do need a well trained dog that is at the very least steady to game and quiet. The GC tests only use dummies, or possibly some cold game at level 5, so they aren't all that relevant to an actual shoot, especially for spaniels/beating dogs where you need to be sure your dog is steady enough to hunt live game, stop to flush etc. but the basic training principles are good. I did them with Ro as a bit of fun but they weren't anything like actually taking him shooting which is what all his training was tailored to.