In my defense, I still eschew html as far as possible. Even when I use html the messages are multipart, and the text versions usually are complete. I do this thing when I reply where I open the gmail menu, switch to plain text and then switch back to html. This has the effect of stripping out all styling from the message I am replying to, replacing html block quotes with conventional '>'s, and so on. That makes it easier for me to quote passages and so on.
I think of it as 99%[1] text/html with format=flowed, and if gmail ever added format=flowed to text mode[2] I'd switch back in a heartbeat.
[1] The remaining 1% of the time I'm composing something long enough that it has more in common with publishing than 1-1 communication.
[2] I wouldn't hold my breath: http://productforums.google.com/d/topic/gmail/Z42NibAOzjc/di.... More likely I'll stop using gmail one of these years..