I do not believe this behavior has changed at all. If the value of your properties are not updated and reflected on the clipboard, then your declare expressions will not fire. So in this use case, yes, you would still need to post your values to the server.
But at the same time if you have declare expression in Work class there is automatic posting of value there is no explicit post or refresh required. If you just tab out then and there only declare expression will fire.
I understand that there is an inconsistency here. But the data that I have found, is that this is by design for performance reasons. If you need further reasoning and/or to have an SME validate my understanding/findings I can engage a moderator to tap someone else. Because I could be incorrect, or maybe the feature has since been enhanced in a later release.