One thing I've been wondering is how each quarterback stacks up with regards to performance in different areas of the field. Just a simple passing chart with the width of the field divided into thirds and length of passes categorized as 0-10 yards, 11-20 yards and 20+ yards.
It's obvious that the coaches want Waters in there to take pressure off of the run game, but more importantly to get it to the deep threats downfield. Is he markedly better over a large portion of the chart, or areas of the field in general? He should have to be to take most of the snaps, imo. We can't watch practice, so we can't judge there. And obviously the smallish sample size for Sams would yield skeptical results when looking at a passing chart.
You might even be able to say that generally Sams would be more ideal for a Snyder offense, but that with this particular group getting the ball to Lockett, and to a lesser extent, the other pass catchers Waters' skills are more valued. That obviously does not settle the debate over whether or not Waters' passing game is actually that much better than Sams' is. I would wager to say that it probably is, I don't imagine that the coaches would deliberately put the wrong guy out there time after time.