It's only a safety valve against high temps if you consider cooking at 300 degrees a failure. It's not failing at all no matter what some so called experts say. Using water with kingsford, it's difficult if not impossible to maintain 300+ in a WSM or UDS. So any type of hot n fast cook is out of the question.
Now if you feel you can't make good BBQ cooking at higher temps, water is for you. For me, it's a waste of fuel energy in any cooker.
Modded Brinkmann Gourmet. Basic UDS. Rescued 22.5" OTS. SJS Mini-WSM. Stubbs. B&B Oak Lump.
Cannondale 2009 F8 (for burning off all the great BBQ)