if you work up to one heavy triple where the 3rd rep is an all out exertion and you can't do another, then I don't feel that is optimal for hypertrophy, but if it is a weight you can handle for 10 sets of 3 and get all your reps and still work hard, and it takes no longer to complete the 10x3 than it would for you to do 3 sets of 10, the body is still doing 30 total reps with a weight. And if you're progressing the weight eash session and keeping sets/reps constant, then hypertrophy will occur, and this is more effective than blindly pumping away on all sorts of exercises just trying to hit '8-12' reps because that is a 'hypertrophy range' and keep the muscle under tension and force blood to the area, etc, etc.