Can't agree with the usefulness of the restrictions in this form. The time spent on the forum - it is possible. But to limit the message, forcing them to write - this is absurd. You can think of the forum is the secret sections. Or spammers can't write in the newbies section. In the end, it forces the newbies spamming, no more than that.

Ссылки со всех ресурсов о биткоине ведут сюда 

Hmm... the best result is 550 at least on stock clocks.