Interesting concept.<p>I tried it out and got the 'We've sent an email to foo@example.com with a confirmation link.' message. It's been about 5 minutes and I still haven't received the confirmation message. You might want to turn some knobs so that the confirmation emails go through sooner.<p>Or are the confirmation emails similarly intentionally delayed? :)
Sortof related: I just wanted to add that many MTA's <i>email servers</i> also support this concept. Using milters or scripts, you can default emails to be stored in the hold queue, then release them based on ingestion time.
I'm loath to mention this, but although I assume the use of "tard" in the name is to signify delay, some might be sensitive to that term.
Instant messaging has become the standard. The messages I send my good friends have become shorter, and are often based on my expectations of their reply. With TardaMail, I wanted to recreate the letter-writing experience, digitally. Taking more time to write someone without expecting an instant reply can be very valuable, especially in these times of isolation.