Jhaelen said:
I think you may want to define your definition of 'definition'...
Sure thing.
def·i·ni·tion /ˌdɛfəˈnɪʃən/ [def-uh-nish-uhn] –noun
1. the act of defining or making definite, distinct, or clear.
Varying Degrees of Cover
In some cases, cover may provide a greater bonus to AC and Reflex saves. In such situations the normal cover bonuses to AC and Reflex saves can be doubled (to +8 and +4, respectively). A creature with this improved cover effectively gains improved evasion against any attack to which the Reflex save bonus applies. Furthermore, improved cover provides a +10 bonus on Hide checks.
This is not a complete definition; it is unclear. It says that, yes, the AC bonuses can double in some cases. But it does not define those cases. In this example, we're left with a useless rule, due to the fact that it is incomplete. A complete definition would be something like the following:
"If more than half of the target's body is behind cover, the normal cover bonuses to AC and Reflex saves can be doubled (to +8 and +4, respectively). A creature with this improved cover effectively gains improved evasion against any attack to which the Reflex save bonus applies. Furthermore, improved cover provides a +10 bonus on Hide checks."
This defines the modifier and the times at which it would come into play.
This:
Pick any corner of the attacker's square. Draw lines to each corner of the target's square. If there are one or two corners blocked on these lines, the target has cover; if there are three blocked, the target has [superior] cover.
... is a true definition. And thank you to MindWanderer for pointing it out. It's a shame that one has to go outside the official product to learn the rules for the product. Now, if I have somehow missed rules for cover in the product itself (other than the foliage for the King's Road, whcih provides normal cover), then I apologize and would like to be pointed to the page