I have a naive question about seat angles. In the olden days when I had a Peugeot and a Brooks saddle, you could adjust the saddle angle by these grooved round things. You could also move the saddle forward and backwards, and of course up and down. My new bicycle (a specialized tricross) has a clamp that clamps over the 2 rails on the saddle. You can adjust forwards and backwards, but not the tilt/angle. Just wondering if I'm missing something!