" You use this crappy service either because:
- You didn't spend enough time thinking about that email because you either want to edit it later, or delete it from my mail box
- You expect me to answer by some specific date, which implies you want me to be on your schedule.
- You want to violate my privacy by tracking if and when I read your email.
You also require me to use a third-party service to read your email as a text. That's unacceptable.
Remember you're trying to contact me, no the other way around. Send it plain text or don't send it at all. "