One might think that the following is true (this is a version of “moral rationalism” — not Portmore’s version, but a better version that I have invented and framed in my own way):
(1) If, after all of the moral reasons (including those associated with specific moral requirements) are considered, what morality requires of one is that one PHI (perhaps keep one’s word), then one has decisively most reason — not just decisively most moral reason — to A.
You might think this is true because moral reasons (or the collective or resultant verdict of the moral reasons) is never outweighed by countervailing non-moral reasons (or their collective or resultant verdict). Or — I think much more plausibly — one might think  is true because ‘morally required’ or ‘what morality requires of one’, when used to refer to requirement-type resultant valence, as a conceptual or definitional matter, already include the non-moral considerations in the “calculation” of the resultant valence. On this view, one is not saying anything substantive about the relative strengths of non-moral (e.g., personal, self-interested, parochial) and moral reasons (including the reasons associated with specific moral requirements). If you think we live in a world in which super-strong moral reasons regularly swamp the moral reasons (including those associated with specific moral requirements), then you won’t think very many things are all-in morally required (and probably, based on similar conceptual considerations, you won’t think that many putative specific moral requirements are really moral requirements, since the associated reasons will not carry the day decisively in large ranges of typical choice situations).
An old-school analyst would say that this makes (this version of) moral rationalism “trivially true.” I don’t think that , if it is true in this way, is trivially true. For it tells us something important about the reasons or specific valences (and hence ends) that being morally required (the non-specific, resultant valence) takes into account. The non-moral reasons are already baked in, this is not obvious, and we can and do get confused about it.