Today I updated my 15-inch MacBook PRO Retina to SMC 1.2. I noticed that when MacBook started after updated it blew dust out of the cooling fans. My table was full of dust (not a lot but still more than noticeable). It is just one strong blow and then it becomes silent again. I noticed the same thing when update SMC 1.1 come out a while ago. Then I thought it was some kind of glitch but now I see that this is like "feature" and Apple uses it for purpose. Does anyone know more about it and can it be initialized manually just to clean cooling fans. It would be very useful since SMC updates are not so often.