Is it permissible to let the hands hang down then place them on the chest after the opening Takbeer, and does this contradict the Companion's command to place the right hand over the left in prayer?

It has not been reported from the Prophet, peace and blessings be upon him, that he let his arms hang down after the opening takbir (takbirat al-ihram) and then placed them on his chest. Rather, it has been reported that he, peace and blessings be upon him, raised his hands when he entered the prayer and pronounced the takbir, then wrapped himself in his garment, then placed his right hand over his left. And the people were commanded that a man should place his right hand on his left forearm during prayer.