Native ofs format appears to be broken.
This format is little-used, but relying on raw stream operators for the native format breaks down when different face types (face vs. triFace vs. labelledFace) are being used. It is still reasonable to have stream operators for pass around data (eg, between processors), but they shouldn't be used for files. Otherwise we can easily create a binary file using triFace or labelledFace and not be able to read it back with normal face.
Additionally, the static OFSsurfaceFormat::read functions are too fragile (broken).
Suggest removing entirely. @andy