Let me ask you something:
Let's say in your line of work, you and someone else is up for a promotion....and you clearly outperform the other person in a 4 week stretch...but the other person joined the company with a higher salary and was younger....and they just handed the promotion to that person....
Is that fair? Would that sit well with you and your co-workers???
What I am trying to get at is, based on last year's preseason results, it was clear as day KH earned the starting job, and yet it was handed to JP. How does that sit with the vets? I'm sure not well. See players want to win NOW...the average NFL career lasts 4 years, they are in this business to win right now...
Plus if the Head Coach makes his decision based on performance, that earns trust with the players. If the coach bases it on youth, etc...how can the players trust the coach?
Now granted, are the Bills a team, when looking at it as of now, going to win the Super Bowl? 99.9% that is a no...but players compete to win, they do not sit around and say "well, since Mort says we have no chance, why bother?"
Bottom line: If Nall or KH clearly outperform JP in the preseason, they should start.