It is an interesting theory that consecration does not carry with it jurisdiction. Consider the hypothetical: The Conclave elects a deacon as pope. He says accepto to the Cardinal Deacon. At that point it seems that he becomes pope. But what if he refuses to be consecrated a bishop. Let us say that out of humility he wants to remain a deacon. Ok, so now he rules the Church as a deacon and he carries the title "Bishop of Rome" even though he is a deacon.
Who is going to tell him, "Excuse me, you must be consecrated a bishop if you want to be pope"?