There's little point in starting someone week 1, and yanking him out by week 4. Teams that do that typically have made a bad and wrong evaluation on the week 1 starter.
Don't think that will happen to this front office and coaching staff.
Ballard has now had several opportunities to endorse JB as the starting QB for next week. He's shied away from doing so every time. His 'I thought Luck was going to be the starter, so I'm not sure' line is a cop out, it's his way of wriggling off the hook.
Also, the way Ballard, Reich and Sirianni all have talked about what they value in a QB is interesting. It reminds me of what Commodus said to his father in Gladiator: None of my virtues were on your list. It's like hearing your significant other describe what they find attractive and realizing that they're describing someone other than you.