I'm curious why myself. So I moved your thread to the bricked section in hopes it will get the attention of mauifrog or someone else that might have a theory. This is the second brick I have seen when going from Priiloader .3 to .6. Hopefully it's a coincidence and not a bug.
BTW: I'm glad you was able to fix yours. The first one I saw bricked in this manner, I had to flash the nand for the user.