I know I've asked before, but I'm wondering if anything has changed on this

Common complaints about Groupwise after we migrated from .psts is that the
attachments get edited in the temp folder and then get lost. In other
words, you cannot edit from within the email client.

Does this same limitation still exist in Exchange? Also, is this a result
of the collaborative servers having only one copy of the attachment in their
database? Users cannot edit the original doc because that would modify it
for all recipients?

And is there a workaround for that? Like Sharepoint? Or routing maybe?