An alternative scheme is outlined to explain acetamide formation routes in the ISM; kinetically, tunnelling in a 1,3[H]-transfer reaction from a higher-energy isomer, ethanimidic acid, seems to offer a possible channel which is probably more reasonable than the current examples A general mechanism is then needed to generate this imidic acid from more abundant precursors and it is proposed that an acid-induced water addition to carbon-nitrogen triple bonds, hosted on water-ice grains, not the gas-phase, of R -C ---N H2O ---→ H3O + RC(OH) --NH, meets this requirement. The auto-catalytic nature of this reaction is a point in its favour as well as the fact that the more direct addition R -C ---N H2O --→ RC(OH) --NH has been discounted. Since this system exhibits quite a range of bonding, even within the restrictive context of neutral and closed-shell molecules, the results are likely to be useful for incorporation into databases for artificial intelligence learning/predictive efforts -ameliorating the well-known problem of dataset bias.