The new Sender Information feature in Mail Delegation in Gmail

Discussed here - Mail Delegation in Gmail, which is considered the safest way to allow someone access to our accounts, has recently received a new feature. 

Previously, under the Gmail settings > Accounts & Import tab > Grant access to your account section, we would only get the "Mark as read" option. 

Now, there is an additional section titled Sender information where the owner of the source account has the option to determine whether messages sent from the delegate account(s) will include attribution or not.

Note: The options can be changed anytime by the owner of the source account. There is no need to click on the Save changes button. The changes are automatic upon selection of the respective radio button.

For the recipient, here are the basic differences depending on the option selected:

In the Gmail web UI

In the message header