So in essence even if the forum have some measures of pardon to higher rank members with good reputation the user will still get his/her punishment with possible signature ban for a timeframe, this still bowl down to the truth that bitcointalk have zero space for plagiarism no matter how minimal or unintentionally the plagiarism is committed.
Theymos mentioned that each and every plagiarism case will be handled individually, so if someone commits plagiarism before 5 years and their accounts got reported today for permanent ban then they maybe taken into consideration about their presence here does made any changes and something like that.