[Nate Paymer]

“Vision” is currently defined as one of the six marking violations in 18.1. I think it should be rewritten as a general violation, without a specific name, as it was in the USA Ultimate 10th edition rules:

> Deliberately blocking a thrower’s vision is a violation by the marker and can only be called by the thrower.

The cost of adding a call with a specific name — in terms of how difficult it makes the rules to understand, memorize, and apply during a game — is fairly high. The rules could define a separate word for every single clause in the rulebook, but then we’d have to all learn 100 different words that apply in specific situations. Instead, they wisely define a few words for common violations, and let the general “violation” call cover uncommon situations.

This is especially true for marking violations, because unlike calls that stop play, players don’t get the benefit of a stoppage of play to think about how to respond. So the bar for adding a specific word for a marking violation should be even higher than it is for violations that stop play.

I have been playing ultimate for 20 years, and I have *literally never* seen “vision” called on the field. It is just not a common situation.

Finally, unlike the other marking violations, intentionally blocking the thrower’s vision is unlikely to happen “accidentally.” A player deliberately blocking the thrower’s vision is likely to be relatively unfamiliar with the rules. And a player unfamiliar with the rules is unlikely to respond appropriately to the thrower calling a marking violation. So in practice, this call is likely to simply cause confusion. Better to stop play and explain the rule, rather than making a call that the marker does not understand.

In summary, “vision” as a separate marking violation adds needless complexity to the rules, making them harder to learn and apply on the field without any appreciable benefit. I think it should be rewritten as a general violation.