I have just completed a paper (unpublished, 10 pages) entitled : "Is Mass Spectrometry Accurate?" The pdf file of the paper is may be downloaded at my website. Our nuclear physics theory on nuclear binding energy is all wrong. The current concept of nuclear mass defect is wrong. The reason why the nuclear masses don't add up correctly in nuclear fission is because the the atomic mass provided by NIST is all wrong! Yes, the most prestigious of equipment, the Penning trap, cannot weigh atoms correctly! It could provide high precision indeed - to 10¯¹⁰ , but precision is not the same as accuracy