(It is cited in note 63 in the pamphlet on matters of migo that appears on the site.)

I have criticized Rabbi Dessler’s words in several places. There they were brought as an illustration of the idea of legal truth, but that does not mean there is agreement with his view.

There are two reasons to reject falsehood. A. Because it is not the factual truth. B. Because saying something false causes a distortion of judgment.

So, for example, when Jacob says to Isaac, “I am Esau your firstborn,” there is a failure to state the factual truth, but on the other hand there is a statement that leads to a true judgment, since Jacob is the one fit for the birthright.
There is an opposite case, such as “deception,” where the statement is absolutely true on the factual level, but it causes a distortion of judgment, because the listener understands it differently.
A situation in which one must say something that leads to a true result by means of distorting the factual truth is a constraint that one is obligated to act on, but with a feeling of pain. (And therefore, in the Netziv’s view, there was a claim against Jacob—not about the act itself, but about the lack of a sense of pain.)
With blessings, S. Z. Levinger

In this week’s Torah portion Jacob says to his father, “I am Esau your firstborn,” and Rashi explains: “I am the one bringing it to you, and Esau is your firstborn.” I never understood this cleverness. If the speaker assumes that the listener will understand the false meaning, what is gained by saying the words in a way that could be interpreted differently?

True, there are various interpretations that go more deeply into this issue, but I have never been satisfied.

There is also a school of thought that holds that for it to be permitted to lie, two conditions must be met: first, that one alters for the sake of peace; second, that one alters in a way that can be understood in two ways. And I have never fully understood: if there is permission to alter for the sake of peace, why is there an obligation to say it דווקא in a way that can be understood in two ways? And if “can be understood in two ways” is itself a permission, why only where there is “peace-making”?

I am attaching an example from a book that fuses the two permissions:
Siddur Shel Shabbat, part 1, root 1, branch 4:
Our Rabbis of blessed memory said (Yevamot 65b), “It is permitted to alter for the sake of peace”; Rabbi Natan says, “It is a commandment to alter,” etc. And nevertheless, Heaven forbid, one should not alter so as to utter an actual falsehood with his tongue, but only in the manner that Jacob said, “I am Esau your firstborn; I have done,” etc., about which Rashi of blessed memory explained there: “I am the one bringing it to you, and Esau is your firstborn; I have done as you told me.” And so too the statement of King David to his young men, that they should say in his name to Nabal, “So to the living, and peace be to you,” etc., is explained (in the holy Zohar, Vayishlach 171b): “But has it not been said that it is forbidden to greet the wicked first with peace?” etc. Rather, this has been established as referring to the Holy One, blessed be He, and “Nabal” was regarded as referring to him, etc. And similarly in the servant’s account he said, “And I asked her,” meaning at that time when I asked her, “and I placed the nose-ring,” at the time when I placed the nose-ring. And if Laban’s heart did not understand his intention, there is no prohibition in this. And likewise our Rabbis of blessed memory said (Bava Metzia 23b), regarding these three matters the Rabbis are accustomed to alter their words, etc. They were careful to say “alter their words,” and did not say they are accustomed to lie, because Heaven forbid that for any reason or cause they would utter a falsehood, Heaven forbid, in their words; “the remnant of Israel shall not speak falsehood.” And the seal of the Holy One, blessed be He, is truth. And one who lies, as is known to those who know grace, lies, Heaven forbid, with the King’s seal. Rather, they only alter their words so that in his heart he understands himself to be saying things that can be understood in two ways, and he intends the truth; and if the listener heard and erred, there is no prohibition in that. And this is specifically in those three matters or for the sake of peace as stated, but in other matters that are not for the sake of a commandment, certainly even this is forbidden. And such was Eliezer’s alteration, all in order to conceal from Laban and Bethuel the awesome virtues he saw in her, so that they would send her with him, and peace would be made for her by bringing her to her husband’s home.

The conception expressed in this rabbinic midrash is that the prohibition of falsehood has two components:
1. The very act of uttering something false, regardless of the other person’s understanding. This is not an offense between one person and another, but the value of truth as such.
2. Between one person and another—misleading the other person. Their claim is that component 1 is lighter if one utters something that is not false on the literal level.
I am not sure I agree with this conception.
It is possible, however, that component 1 is also connected to an interpersonal prohibition, except that it has educational significance. If a person accustoms himself to denounce falsehood as such, that will educate him not to lie. Therefore there is value in this too: even if you are forced to lie, it is preferable that you give yourself an educational reminder that it is not okay, and try to do it in the form of an “alteration,” meaning with the appearance of truthful speech.