OK Fuji, we'll differ. I was passing on briefing from my instructor that worked surprisingly well for me.
As I said before, a flick of the eyes down to altimeter is helpful when you are learning, and IMHO that is all the is required otherewise you will over use the instruments.
As a low-hours student, I don't yet have an intuitive ability to maintain balance, especially when flying unusual and energetic manoeuvres. So I have to check the balance ball. Same for throttle setting, so I have to check (just once or twice) that the speed isn't dropping towards the increased stall speed. The instructor asked for a 180 or a 360 and ground references weren't the clearest due to haze, so I had to use the DI to help maintain orientation.
Out of interest, how is the steep turn examined on the skills test? Does the examiner typically ask for a turn through a specified angle (e.g. a 180), or onto a heading? Or is it just to be held until the examiner asks the candidate to roll out?
I agree that in good VMC, I should ultimately aim to be able to do the manouevre without reference to instruments.