But if you wrote an email template app based on tables, why would you change it if it's not broken? Why would you go through the hassle and expense of redeveloping your app just to not use tables? No sane person looks at the HTML of an email. Only poor souls that get a request on how to send email spam in-house might ever consider it, or just the perversely curious. Either way, nobody cares what it looks like under the hood as long as it looks good when viewed in the client.