As an aside, it was Hitler’s original intention (as I recall reading history) to win the Presidency in order to dismantle the Weimar Republic from the top down. Hindenburg stood in the way and had little regard for Hitler, who he viewed as an incompetent Corporal of World War I and a gasbag.
Too bad Hindenburg didn’t stand his ground instead of allowing himself to be pressured into naming Hitler to the Chancellor’s position.
The Presidency was not the key to this process: the Chancellorship was.
The President was not permitted dictatorial power, but he was permitted to give the Chancellor dictatorial power.
Hitler did not want to grant someone else dictatorial power - he wanted to have dictatorial power.