I could be wrong, but the way I understand the Coryell offense recievers likely only have option routes when they are the designated option route runners. Let's look at what I do know
The Coryell offense is like a jigsaw puzzle. All the routes fit together to force the defense to cover the maximum amount of the field.
here it is visually
See how each route is detailed and they all fit together to accomplish a unified purpose, creating an open space for the f-post receiver to exploit?
Here’s the description of the F-Post from Blood Sweat Chalk.
The most common call was 525 F Post Swing. Both outside receivers would run 15-yard outside comeback routes, carrying the corners to the outside. The Y receiver would run a 20, or a shallow cross, occupying the vision of the linebackers and safeties. The F receiver—sometimes a running back, sometimes a second tight end, depending on the formation—would then run an option post route, finding his own open path. A running back would run a short swing pattern. "It got to be an unbelievable play, the best play in the whole system," says Zampese. "And they still run it."
The routes fit together to create a killer play. The outside receivers need to get 15 yards downfield and to occupy the corners and the Y receiver needs to run the cross to occupy the LB and safety. The routes work together to clear an open space so the F-post receiver can run any of 3 routes. If one of the receivers is freelancing it throws of the spacing of the play.
From BSC on the importance of spacing
"The spacing element of the Coryell offense—in which every route is designed to maximize distance receivers, making them more difficult to cover—has its roots in the Dutch Meyer book that Coryell studied. "It’s one of the huge keys to the entire offense—the spacing is just so important," says quarterback Kurt Warner, who operated the system for the Rams. "It’s so emphasized to all the receivers: Get off the ball and get downfield, get great separation between your deep route and your six- to eight-yard route. The entire offense is very precise, and it comes down to spacing more than anything else, spreading out the defense." If the Coryell system is executed properly, as with any spread-style offense, defenders are forced to cover huge chunks of earth to blanket receivers."
Receivers in the Coryell offense don’t freelance. In fact, freelancing is discouraged. Again from BSC …
The final component was timing; from the early days Coryell harped on the wedding of speed and precision. "We put a timing element on every one of the routes," says Zampese. "Say we were asking the X receiver to run a 1 route. We would tell the guy, ‘Three steps, and when your third inside foot hits the ground, that’s when you break! Just go ahead and change direction. No fakes, just timing. Third inside foot and break.’ And the key was to run as fast as you can. Which we forced these guys to do. We told them not to round off their cuts, but we had them running the routes so fast that they had to round them off a little bit."
If receivers were picking their own routes from the entire route tree they’d constantly be throwing off play design. Therefore I think it’s unlikely that any receiver has complete latitude to run any route. It’s inherent in the design of the offense that the receivers don’t have a lot of latitude.
I think it is probably true is that Dallas runs a lot of plays where Witten is the receiver that has the option route. But on plays where Witten is not the option route he probably has a specific route to run.
p.s. there is an offense that has multiple option routes. it's called the run and shoot. More BSC.
All of the elemental run-and-shoot plays involved option—or readable—pass routes, where the receiver is reacting to the defense and the quarterback is reading the receiver. Says Davis, “I get to keep the chalk even after I snap the ball.”