Forgeting Emails

[mesmerized]

I've been listening to the email slave file a lot lately and I think it is working well. I have had contact with someone and their email triggered me with great effect.
But I have a couple of questions about this file:
Firstly:
My received email did not include the "must do" trigger, but if you received an email with the "must do" instruction how does it work correctly because all you have to do is reread the email from your In box or read what you sent out as a result of any instruction received and your reminded.
Is it possible to include within the email sent to the subject an instruction to have them delete the email they are reading, while maintaining a note of the return address to be used and also any email they sent out in response. If so shouldn't this type of instruction be included in any email instruction that the hynodomme wishes to keep secret from the subject.
or maybe once the hynodomme has received the required response they could send a separate email making the subject erase all traces of it.

Secondly:
Do all emails received only work the once. I have reread my received email instruction and it did not re-trigger it. Is it a once only thing or could some people keep being re-trigger.