you can run any offense or defense if you've got stud players and you will have success. There is truth to the idea that stars make coaches look better, no question, but coaches can guide average players into being fundamentally sound and create a culture that affords the team consistency over time. There's definitely a balance.
Receivers are a unique bunch. I've seen good ones go into slumps. Don't know that Cahoon can be completely blamed for dropped balls.