I do not think this can really be considered "shaming" as it's nothing to be embarrassed about.

Regarding private/public notification; Posting to your own account is an easily understandable visible demonstration of what's possible and why you should care - a DM from another account, or an @ just won't have the same effect on the user.

(I have said this elsewhere in the thread, so apologies for repetition)

I have been informed that it's possible to send a DM to yourself, so I'll add that as an option shortly as a nice alternative.