I was talking to someone a few weeks ago, who said he never includes doctypes in his HTML newsletters, because it is not necessary. I thought to myself "How can it not be necessary? The newsletter still needs to be rendered by a rendering engine, which needs to know how to interpret it".
So my question - Are doctypes necessary for an email newsletter? If so, what doctype is recommended? For compatability, should HTML 4.01 be used over XHTML served as text/html?
I'd say that it definitely makes a difference.
I just pefected a template in CM with an HTML 4.01 Transitional doctype. Then I integrated it into the client's mailer app, which doesn't output a doctype at all.
Now the font size of various text blocks is larger than it should be, which is problematic because it only affects some email clients...
Campaign Monitor sends in UTF-8 format, so if you are importing into your account, that's the doctype you want to use. Also, we certainly see lots of variations in browsers based on Doctypes, and now that there are so many web based email clients, you would expect to see that impact if nothing else.
Oh, totally. I'm not pointing the finger at CM at all. The mail app the client uses is a real dinosaur, and I have no control over doctype or charset AFAIK. I think the client plans to trial CM for a campaign in the near future so hopefully these headaches will soon be a thing of the past :)