Pre blanching the rice allows for a properly cooked risotto,
(with the rice fully but not over cooked) that has a creamy
texture, is moist. It allows the live part of cooking
to be dramatically reduced in time, from 20 - 25 minutes
to 10 minutes.
It must be remembered that cooking a risotto is a 'live'
event, it must be continually moved, stirred to allow
even cooking of all the rice granules.