2 Kings 20-21

In 2 Kings 20 we read how king Hezekiah is sick and it was God's plan that he should not recover. But his prayer of sorrow by the king led God to change his plan. Hezekiah asked for a sign of confirmation. God offered him a choice; moving the shadow forward or backward on the steps. Hezekiah chose the "harder" of the two and the shadow moved backward. Indicating that there was nothing that God could not accomplish. But I wonder how the shadow moving forward would have been a sign? I don't think that Hezekiah showed a lack of faith in his choice. Yet why did God offer the first choice? it could be that Paul's words in Romans 1:20 show us that God's first stated sign is also a clear indication of his power. The orderly operation of creation is just as spectacular as any miracle.
Stuart