This thread is very helpful and it teaches you about madmans.
According to that thread
Originally Posted by Pirate
2: head dismembers generally come later in the replay, although starting with the head dismember is not looked down upon in any way.
My Answer,
No, it only makes your replay cooler, a replay is considered a madman when one dismembers 5 or more joints so its not really important to decap it depends on the replay maker.
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