I have no idea if it's popular, but I'd guess not. It's not exciting, but then fans wanted Ricky Proehl as WR coach (clearly, that means Shipley should be the next one). They wanted Spurrier and got Fox. Those are extremes, but I don't think it's damning that he's an existing coach.
They've done well with most hires like this. They did just this with Crossman, but Crossman wasn't shitty because he was an internal hire (and truthfully they got him with a top resume' - I never figured he'd be this bad). He was shitty because he was shitty.
I guess it depends on whether you want to say he's the next Crossman because he took the same path. I would've preferred an outside hire, but sometimes change is change.