Backbends are to be felt more than expressed. The other postures can be expressed and then felt. Like in meditation each person has to feel backbends.
B.K.S. IyengarLook after the root of the tree, and the fragrant flower and luscious fruits will grow by themselves. Look after the health of the body, and the fragrance of the mind and richness of the spirit will follow.
B.K.S. Iyengar