Hi!
Since the use case that you're proposing below is for a series of one off email sends, I would suggest building out nested email programs underneath your webinar program so that you can leverage the full capabilities of the A/B testing available within an email program. Understanding Email Programs - Nesting
You could also use Champion/Challenger in this use case, but in order for it to work, the smart campaign has to be a trigger based send, not a batch. If you set it up as a batch send, the A/B test won't work correctly. Champion/Challenger Emails Explained At the end of the Champion/Challenger test period, it will ask you to declare a winner, but you don't have to do complete this step if you aren't leveraging the same email for future sends. Hope this helps.
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