I posted this in response to: https://techcommunity.microsoft.com/t5/Office-365-Groups/Feature-update-Email-sending-behavior-for-G.... But it deserves to be a conversation in it's own right.
The whole thrust of changes in the post above seems to be about making Group messages behave more like Shared Mailboxes than Distribution Lists. Mail sent to a shared mailbox does not end up in the senders inbox (unless CC'd); mail sent to a DL does.
Microsoft have got groups all wrong. They should be an enhancement to Shared Mailboxes, not a replacement for DLs. Shared mailboxes centralise messages and anyone with access can see the whole mail history, both received and sent (if Outlook is setup properly).
We've always encouraged clients to use shared mailboxes rather than DLs for group addresses (see what I did there!). Much more sensible for clients to receive the mail once and see when it has been read and responses to it. Behind a Group is a shared mailbox, just most of it hidden. That makes no sense. Groups should expose the whole shared mailbox as normal. Then there'd be no need for group messages to behave differently in Outlook. If people want "conversations" (i.e. something more like IM), they can use SharePoint or Yammer.
Adding shared files and notes to what was a basic shared mailbox makes a whole lot more sense than messing about with DLs, which by their very nature are extremely simple constructs designed for one purpose - to send mails to multiple recipients.
As it stands, groups may have a use for internal communications on a particular subject, but they're no good for external communications where the full functionality of the shared mailbox is needed.
I urge Microsoft to consider Groups an enhancement to Shared Mailboxes, not DLs. Essentially that means you just need to back-out the changes made for Groups in Outlook and instead expose the full shared mailbox as normal. That then makes Groups a great tool to use for both internal and external communications and collaboration, with very easy management by end-users through Outlook.
The one thing you do need to fix is mobile access to shared mailboxes. It's incredible that we still can't access shared mailboxes on mobile devices.
