> The plain email—which took no time to design or code—was opened by more recipients and had 3.3x more clicks than the designed email. I think this result needs more investigation. We need to know why people open plain email more than those fancy designed ones, rather than just having those numbers. Designed email, for a lot of companies, is a matter of style, a VI (Visual Identity) for the receiver to remember. It's…
This is interesting. Would you have questioned the numbers if they showed the inverse (ie designed emails have higher click rates)?
> a well-designed email could increase the efficiency of email reading as you may already familiar with some email and their layouts
I don't think this is true at all. IMO test emails are /much/ more easy to read, because I can use a consistent font and layout for /all/ my emails instead of reading through every designers view.
> emails which heavily polluted with contents that have nothing to do with me
Yes text or designed emails don't change any of the contents and spam still is spam. Marking as spam and removing is probably the best option :)