Why does Rashi omit the word milchemet?

Summary: The first time, Rashi refers to milchemet Amalek. The second time, just Amalek. Why the difference?

Post: While looking through a manuscript of Rashi (Roma, 1470), I noticed the following correction:

Note how in the second instance, the scribe wrote "and in the battle of Amalek", in parallel to the first Rashi on Yisro. Then, dots over each letter to indicate that it is an error. And finally, a strikethrough, to indicate the same. I would assume that it was an error influenced by that first Rashi, rather than being original and corrected based on other versions of Rashi which had accidentally omitted the word.

Does this make any semantic difference? I would say it does not.

But the Taz actually does note the change, and explains that there is a semantic difference.

"and regarding the well, and Amalek." 'Here he does not mention the battle with Amalek, as above, for the reason I mentioned above. For here he only mentions the salvation of Israel from Amalek by way of miracle, and they prayer of Moshe, which is the boon {tivatan} of Israel, which was not the case above, where it was not talking about the their benefit, but rather of novelties {that Hashem did not introduce for their immediate physical benefit, but rather to show His force -- see here}, and this is the battle which He, Yitbarach, brought upon then in order to demonstrate His wonders.'

I think even had it said umilchemet Amalek it could have referred to Hashem's salvation in that war. Many meforshei Rashi operate under the assumption that Rashi is written with ruach hakodesh, or with extreme care, such that one can make a diyuk from such minor variations in language. (Some take that ruach hakodesh to also establish Rashi as peshat, since Rashi says he is coming to say peshat, such that one cannot advance any peshat at odds with Rashi.) But Rashi is written in ruach hakodesh to the same extent that the words of any Sage and Torah scholar worthy of it are guided in part by Divine Inspiration. That does not mean that one should make such diyukim, or that such diyukim reflect the true intent of Rashi's words.

If I had to provide an explanation for the divergence, it would be this: that if we examine the sources of the first Rashi, we see that the phrase milchemet Amalek is used. In Zevachim 116a:

(שמות יח, א) וישמע יתרו כהן מדין מה שמועה שמע ובא ונתגייר ר' יהושע אומר מלחמת עמלק שמע שהרי כתיב בצדו (שמות יז, יג) ויחלש יהושע את עמלק ואת עמו לפי חרב ר"א המודעי אומר מתן תורה שמע [ובא] שכשניתנה תורה לישראל היה קולו הולך מסוף העולם ועד סופו וכל [מלכי] עובדי כוכבים אחזתן רעדה בהיכליהן ואמרו שירה שנאמר (תהלים כט, ט) ובהיכלו כולו אומר כבוד נתקבצו כולם אצל בלעם הרשע ואמרו לו מה קול ההמון אשר שמענו שמא מבול בא לעולם (אמר להם) (תהלים כט, י) ה' למבול ישב [אמר להם] וישב ה' מלך לעולם כבר נשבע הקב"ה שאינו מביא מבול לעולם אמרו לו מבול של מים אינו מביא אבל מבול של אש מביא שנא' (ישעיהו סו, טז) כי (הנה) באש ה' נשפט אמר להן כבר נשבע שאינו משחית כל בשר ומה קול ההמון הזה ששמענו אמר להם חמדה טובה יש לו בבית גנזיו שהיתה גנוזה אצלו תתקע"ד דורות קודם שנברא העולם וביקש ליתנה לבניו שנאמר (תהלים כט, יא) ה' עוז לעמו יתן [מיד] פתחו כולם ואמרו (תהלים כט, יא) ה' יברך את עמו בשלום ר"א אומר קריעת ים סוף שמע ובא שנא' (יהושע ה, א) ויהי כשמוע כל מלכי האמורי ואף רחב הזונה אמרה לשלוחי יהושע (יהושע ב, י) כי שמענו את אשר הוביש ה' את מי ים סוף

Rashi is, of course, providing a summary and collection of two of the three positions (possibly omitting the third opinion, that it was mattan Torah that Yitro heard, at this early stage, so as to avoid discussion of just when this arrival of Yitro occurred).

Later on, while mentioning the same point, it would not be so strange for Rashi to omit the word. Though I haven't found (though I haven't looked far) mention of Amalek without milchemet, we know what Rashi means already, and so he can afford to be brief. This is not something we should be making a big diyuk out of.

I'd like to also briefly consider the suggestion of Rabbi Chaim Hirschensohn, in Nimukei Yosef:

"In the descending of the manna, in the well, and in Amalek" -- The intent of Rashi, za"l, is to add upon that which was mentioned previously, the splitting of the Reed Sea. But he should not have mentioned again Amalek, for he had already written this once. And it is not farfetched to think that in the manuscript of Rashi, za"l, was the acronym ובמ"מ, which are the first letters of "and in the sweetening of the waters of Mara". And the first mem was switched by the copyist for an ע, for this is an extremely easy switch in Sefardic script, such that they almost have the same form. And this copyist thought that these were the first letters of ובעמלק. And also, in Rashi script, it is easy to arrive at this switch. For indeed, it is difficult why Rashi does not mention the sweetening of the waters of Mara. Rather, certainly he wrote it with this acronym above the line, and it should have come before the descending of the manna, but because of the switching of the mem with the ayin which the copyist believed was a shorthand for בעמלק, he entered it after the well. And if the matter is such, we need to order the nusach as אשר עשה במתיקת מי מרה בירידת המן ובבאר.

While the Nimukei Rashi believes that this is not far-fetched, it seems to me to be farfetched in the extreme. First, ובמתיקת is a very strange word to make into roshei teivos, and especially ones which don't have the first root letter, but just וב. Then, to posit not only a switch by a copyist, but a movement to another place seems difficult, as is the assumption that it was first placed above the line, so as to enable the copyist to make this decision. Finally, if we look at Rashi's midrashic sources, the Mechilta mentions in close order the war with Amalek, the manna, and the well:

בדרך - זו מלחמת עמלק.

ויצילם ה' - הצילם המקום מכל.

[יח, ט] ויחד יתרו - ר' יהושע אומר:
בטובת המן הכתוב מדבר.
אמר לו: המן הזה שנתן לנו המקום אנו טועמין בו:
טעם הפת.
טעם בשר,
טעם דגים.
טעם חגבים.
טעם כל המטעמים שבעולם,
שנאמר: טובה הטובה, כל הטובה על כל הטובה.

ר' אלעזר המודעי אומר:
בטובת הבאר הכתוב מדבר.
אמרו לו: הבאר שנתן לנו המקום, אנו טועמין בו:
טעם יין ישן,
וטעם יין חדש,
וטעם חלב,
וטעם דבש,
טעם כל המתוקים שבעולם,
שנאמר: טובה הטובה, כל הטובה על כל הטובה.

I don't find any midrashic mention of the sweetening of the waters of Mara in this context. If he could provide a midrashic source (or better, produce some intermediate manuscript for his conjecture -- Yosef Daas certainly makes no mention of it), it would be a different matter. But as it stands, I don't think Rashi makes up any detail, but draws all such details from midrash, and so I don't believe in the existence of this Ur-text of Rashi.

As an aside, this should be a warning against overeager applications of the critical method. I am a big fan of girsology, and have proposed certain emendations which hopefully are better sourced and less-far-fetched. But I am reminded of Shadal who proposed his own emendations of certain Biblical (non-Pentateuchal) texts, but was horrified at the mess that other contemporary scholars were making with their own specious emendations.

If we must grapple with this repetition, then we must grapple with it. What was motivating Rashi to repeat it? What about et kol asher asah prompts Rashi to bring these deeds, and repeat Amalek but not the other? Is there another midrashic source out there, that Rashi is simply citing, that repeats what he had above? I am not sure about Rashi's motivations in writing what he did, but I'm thinking about it.