See 6.4 on Omitted Illustrations. If you were going to omit captions that repeat information in the text, I think you would have a TN that says so. TN Captions that repeat text are omitted. But I don't think you can just omit anything like that without notice. Used to be, but not any more. And consider that including such captions is a way of letting the reader know that there is picture. Part of what the transcriber does is inform the reader about what's on the page. Words alone aren't enough. That's all Formats is, informing the reader about the page. If just the words were enough, we wouldn't need Formats. We could just do the words. That is actually the way it used to be.
--Joanna