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unblock|http://en.wikipedia.org/wiki/Wikipedia:Blocking_policy#When_blocking_may_not_be_used

to quote directly: Disputes

Administrators must not block users with whom they are engaged in a content dispute; instead, they should report the problem to other administrators.

An exception is made when dealing with unsourced or poorly sourced contentious biographical material about living persons. Administrators may enforce the removal of such material with page protection and blocks, even if they have been editing the article themselves. (See the BLP policy.)

Cool-down blocks 
Brief blocks solely for the purpose of ""cooling down"" an angry user should not be used, as they inevitably serve to inflame the situation. 

you had no right to block me for something said on my talk page. please take your vendetta somewhere else. i made a comment two months after the fact with nothing in between i don't see how this warrants a block and it appears to violate wikipedia's blocking policy."