Just make sure you don't set on boot until you are confident your phone is stable. The one and only time I had to do a complete fresh install was when Tiamat was clocked to high and it sent my phone into bootloops.
I can occasionally go to 1228 on Tiamat 4.0.2 (yay HDMI-EDID fix merge!) but usually it will lock up. There's no tangible difference between the two clock speeds on Performance gov. for FPSe, so I really only push it to 1228 to see if it'll lock up. One thing I've learned is to uncheck Set on Boot when overclocking, lol! I have set it to 1190 min/max Performance for days on end (Seidio 3500 ftw!) without a problem. I couldn't care less about benchmarks, so eh!