Unless we add conformance requirements for the preservation of metadata and processing instructions, the less featureful apps will never  be able to round-trip documents with the more featureful apps. Our language should require that. Personally, I believe that the software-as-an-end-point client-side office suites are dinosaurs at the end of their era. They are being finished off by a thousand cuts as users spend less and less time using them and more and more time using other apps, such as web apps. ODF either develops methods for interoperability among all apps or it will die along with the office suites.
E.g., Microsoft knows this and is busily migrating its Office development budget across the Sharepoint/Exchange server hubs to the network. Meanwhile, this TC fiddles with preserving the 1995 software-as-an-endpoint vision.