Prerequisites: Graceful Degradation. Summary of that: Some skills require the entire skill to be correctly used together, and do not degrade well. Other skills still work if you only remember pieces of it, and do degrade well.

Summary of this: The property of graceful degradation is especially relevant for skills which allow groups of people to coordinate with each other. Some things only work if everyone does it, other things work as long as at least one person does it.

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Examples:

American Sign Language is pretty great. It lets me talk while underwater or in a loud concert where I need earplugs. If nobody else knows ASL though, it's pretty useless for communication.
Calling out a play in football is pretty great. It lets the team maneuver the ball to where it needs to go. If nobody else on the team studied the plays though [...]