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Your post is a classic example of a useless shitpost. Please stop responding in threads where the subject is out of your league.
Gmaxwell and others have been advising against brainwallets for a reason... they are not and will never be safe.
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That was not the reason, the reason was and is that humans are bad at producing sufficient entropy for the brainwallet to be random (see the post by franky). This is true for the security of all wallets, if the entropy source sucks a collision is (significantly) more likely.
This should probably be watched by anyone who wants to use a brainwallet:
DEF CON 23 - Ryan Castellucci - Cracking CryptoCurrency Brainwallets. He even posted an update (not entirely sure if the account is genuine):
Ryan Castellucci 6 days ago
The current release of brainflayer is much faster than what I released at DEFCON. Currently, it's only $40 to check 1 trillion passphrases on AWS, which works out to 25 billion per dollar.