I think the Martyrs woulds would say “yes, actions under duress have legal and moral value.” What we do under duress speaks more about what we believe and who we are than at any other time.
Pope Honorius may not have produced an Ex Cathedra teaching, but whether or not he intended to give a “definitive” teaching is debatable.
Look at the section on Pope Honorius again:
(Emphasis is mine throughout.)
Infallibility
Pope Honorius
The charge against Pope Honorius is a double one: that, when appealed to in the Monothelite controversy, he actually taught the Monothelite heresy in his two letters to Sergius; and that he was condemned as a heretic by the Sixth Ecumenical Council, the decrees of which were approved by Leo II. But in the first place it is quite clear from the tone and terms of these letters that, so far from intending to give any final, or ex cathedra, decision on the doctrinal question at issue, Honorius merely tried to allay the rising bitterness of the controversy by securing silence. In the next place, taking the letters as they stand, the very most that can be clearly and incontrovertibly deduced from them is, that
Honorius was not a profound or acute theologian, and that he allowed himself to be confused and misled by the wily Sergius as to what the issue really was and too readily accepted the latter’s misrepresentation of his opponents’ position, to the effect that the assertion of two wills in Christ meant two contrary or discordant wills. Finally, in reference to the condemnation of Honorius as a heretic, it is to be remembered that there is no ecumenical sentence affirming the fact either that Honorius’s letters to Sergius contain heresy, or that they were intended to define the question with which they deal. The sentence passed by the fathers of the council has ecumenical value only in so far as it was approved by Leo II; but, in approving the condemnation of Honorius, his successor adds the very important qualification that he is condemned, not for the doctrinal reason that he taught heresy,
but on the moral ground that he was wanting in the vigilance expected from him in his Apostolic office and thereby allowed a heresy to make headway which he should have crushed in its beginnings. Link: Link:
newadvent.org/cathen/07790a.htm
If I convert to Catholicism and I am expected to submit mind and will to the Pope, even in cases when he is not speaking Ex Cathedra; how would I know if the Pope’s decisions and teachings are legitimate or a result of coercion or the result of a lack of theological talent? How would I know that the Pope would not allow “heresy to make headway which he should have crushed in its beginnings,” just as Pope Honorius did?
The Pope’s position, action, or lack of action in any given situation has far reaching effects, even when he is not speaking Ex Cathedra in matters of Faith and Morals.
Peace and blessings,
Anna