"If this isn't improved upon, it WILL show up later in the year when teams adjust, just like last year."

It will only show up if defenses crowd the line of scrimmage and dare Siemian to throw over the top the way teams did to Brian Griese. Taking what the defense gives you is a smart way to go to keep the sticks moving. I think if defenses think of Siemian as Brian Griese...that bodes well for the Broncos. I think last year teams did not adjust to Siemian as much as teams realized there was no threat from the Bronco rushing attack. Therefore they blitzed a lot...this of course leads to quicker throws which more often than not are going to be shorter.
The Little Guy