Some time ago I have posted "Dynamic vs Static" article
And I whould like to raise it again. Why you need to be shure, that user is authenticated if you have ability to check the result (subscribe to recive notices by mail) and ability to delete unwanted messages.
And there could be some random dictionary to determine is article really from you and not a Spam. You just get 1n world from top of it and insert it in your article as 1st line :)
This way you could collect all notify mails from all blogs and delete messages if only it is without "key word".
Ok ... there whould be some minutes when SPAM message will be visible as a blog message, but no more ! :)
It is dynamic solution.
//please reply to me at uazone dt net