I cooked this for lunch today.  It turned out well despite a big kitchen mishap - I spilled about half the uncooked rice on the floor by accident!!  The cleaning was one big headache but the more annoying part was that I didn't know how much rice was lost...so I was purely working on intuition with the water and stuff.  But thank heavens!  I was shocked to see that the product resembled biriyani!  Even before I opened the cooker, my fiancee who was in the bedroom asked if I was actually making chicken biriyani.