partially answering my own question here, the binary_grub-efi script rejects use for netboot images (as well as hdd coincidentally), so no need to be concerned with compatibility there.
On Wed, 2020-04-08 at 16:05 +0100, jnq...@gmail.com wrote: > Oh, quick addition of something I forgot to put in the below message: > > So in the discussion of #924053 it was suggested that the /.disc/info > based solution would only work for ISO/ISO-hybrid images because this > file was created by xorriso. I added a comment just now pointing out > that in fact this file is created by the binary_disc script, which > generates it for iso, iso-hybrid and hdd image types. > > It does not create any such info for netboot and tar images types, > though. I do not expect the tar image will be booted will it? and > thus > there's no concern there? I really do not know all that much about > netboot, so I do not know whether or not there is a problem there.