you may be remembering a nuance of what happens when the same phrase is used as both an exact match and a broad match keyword in the same account. (As opposed to being used in your account, and also in a competitors account.)
When this is the case, the impression is assigned to the closest match to the actual keyword that a user has searched on.
That probably makes no sense without an example. Thus, below, please find an example!
Say you have these keywords in your account:
polished granite widget
"polished granite widget"
[polished granite widget]
* If I search on the phrase 'polished granite widget', then the exact match gets the impression.
* If I search on the phrase 'polished granite widget desk set' then the phrase match gets the impression
* If I search on the phrase 'polished gray granite widget' then the broad match gets the impression.
Hope that make sense. If not I'll try again later in the day after the coffee has kicked in! :eek: