you can do this ,though keep in mind that your engine has to be hot to do this, you don''t want to try this trick with an cold engine as water will not evaporate in cold oil. and aslong as you do what he said...feed it slowly , the water that comes in contact with the oil WILL evaporate immediatly since the oil is numourous times hotter then the boiling temperature of water.
this trick will work but don't feed more then 16 OZ water at a time and don't do it like every 3000 miles either, it's one of those tricks you might wanna try before rebuilding the motor or to prolong it....