You are banned from submitting to this journal

A few days ago, a newly qualified doctor asked informally if he could submit a 'slightly modified' version of a paper he'd just submitted to my journal to the BMJ. I told him about the evils of multiple submission and warned him that some journal Editors, if they discover the subterfuge, may well ban the author from submitting to their journal for a number of years. This, indeed, was the punishment that an Editor-in-Chief — not amused by a recent case of multiple submission to his journal — suggested at a recent COPE forum. If you misbehave in a restaurant, pub or nightclub, the owner may tell you never to return again. Why not adopt the same policy when authors cause trouble in a journal (e.g., by wasting the reviewers' and Editors' time with multiple submissions)?  Yet how common is the practice of banning authors guilty of misconduct from submitting to a journal, or a family of journals? Is it an effective deterrent to authors? Should the practice be adopted more widely by journal editors and mentioned explicitly somewhere on the Advice for Authors webpage, or are there problems with the practice? I'd be interested to hear the views and experiences of COPE members on this issue. And season's greetings to all!