no it would have exactly the same problem - there's no way to know
whether the destination MTA supports the feature, so there's no way
to guarantee a delivery report.
That's what the Delivery-Alert list is for. If the listed feature isn't
supported, an error is triggered. This is substantially different from
having header fields be ignored as would be the case in the scenario
proposed by Paul -- that would be a silent error.
so the message gets to its destination, and the delivery report feature
isn't supported, so an error is triggered. since the destination doesn't
know what the request is the only reasonable thing to do is to bounce the
message.
dream on.
Keith