Was anyone else so sure through most of the book that Rocky was lying about his fuel reserves?

edit - lying so that he could sacrifice himself and give Grace most of the remainder of his fuel, dooming Rocky to a much much longer journey home

Every time it's brought up Rocky behaves weirdly, gives short answers, or instantly changes the topic.

Even after it's revealed that the reason Rocky had so much astrophage left was because Eridians hadn't discovered Relativity - the conversations are so brief. The strangeness around Rocky's excess fuel is brought up some 4-5 times.. was it really all leading up to the reveal that Grace would get to teach relativity to Rocky?

I suspect in earlier drafts that Rocky grew close to Grace and would sacrifice himself (or a hundred or so years of his life, considering Erid had more time) and his ship in order to save Grace by lying and giving up most of his remaining Astrophage to his new friend - but that it was later changed because it seemed a little too cliche and was a poor twist or something.