Your English is fine. "Discard" means throw away.
And, to "silently discard" is to discard without informing anyone. It means,
for example, that you don't also generate a bounce message, or a notification
to the recipient.
My guess is that the phrase "the domain encourages the recipient(s) to
discard it" is intended to refer to a silent discard.
I don't think any of us expected the recipient to send a notification. I
certainly didn't, since the assumption would be that the message was
probably from a hostile sender.
R's,
John
_______________________________________________
NOTE WELL: This list operates according to
http://mipassoc.org/dkim/ietf-list-rules.html