‘Revocability’ is obviously the opposite of ‘irrevocability,’ but if we are only talking about a starting point amended by significant exceptions, it hardly much matters where we start (and end). If, to take a different example, we translate ‘unconscionable’ as ‘unreasonable’ (for lack of a better corresponding term), that would gloss over important substantive differences at the domestic level, perhaps also leading the way to inappropriate conclusions in an international ‘impracticability’ context. So, what makes the greatest impression, the common core or the differences? Maybe it depends on the direction in which we’re headed ... or on where we’re coming from.