I think i understand what I didnt understand :0)

1)A graveyard spiral bank is increasing throughout the situation, as opposed to a consant bank.

2)The bank angle in a graveyard spiral can/will pass 90 degrees at which point back pressure will obviously point the nose at the ground increasing the rate of descent.

Reading the PHAK it explains it poorly. It really doesnt talk about the dynmaic situation IE increasing bank....rather it tooks about a disoriented pilot returning the aircraft to its orignal bank

Then the PHAK goes on to say pulling back on the yoke increases the rate of descent....without mentioning anything about a 45 degree bank as opposed to 110 degree bank and how back pressure effects the two, not to mention the load factor involved trying to stabilize a descent rate in a 70 degree turn with back pressure alone.