I've yet to see a "well constructed" HTML email that was sent by a human as part of an email conversation.
I've seen plenty of poorly constructed HTML emails sent by people who decided that since they can have twelve different fonts in five sentences, with italics, bold, outline, underline and strikethrough thrown in, they should do so. It's almost like they have set themselves a challenge to use every feature of their email client in every message.
Plain text, on the other hand, always looks sensible, well-formed and well constructed to me. This leaves it to the sender to write something worth the effort of reading.
I've seen plenty of poorly constructed HTML emails sent by people who decided that since they can have twelve different fonts in five sentences, with italics, bold, outline, underline and strikethrough thrown in, they should do so. It's almost like they have set themselves a challenge to use every feature of their email client in every message.
Plain text, on the other hand, always looks sensible, well-formed and well constructed to me. This leaves it to the sender to write something worth the effort of reading.