Quoting Commentary for I Kings 6:27

יודוך, they will crown you. The word is abbreviated in its spelling, being the equivalent of יהודוך, (as in Psalms 45,18) Similar constructions [a letter being omitted, Ed.] are found in Kings II 6,27 where we have יושיעך instead of יהושיעך). The latter and proper spelling is found in Samuel I 17,47 i.e. יחושיע. At any rate, even though the word יודוך is derived from הוד as in הוד מלכות, “regal majesty,” the letter י is not an integral part of the word, but is added as part of the constructions known as חטופי פ'ה, the first root letter in roots commencing with the letter ה being shortened in sound. When we encounter to word הוציא, a transitive past construction derived from the root יצא, the first root letter of יצא has actually been omitted, the letterה in הוציא not being part of the root, but substituting for the letter י of the root. The same is true of the root ישב and the transitive construction of that verb as הושיב. We encounter the same phenomenon in Exodus 15,5 where the Torah wrote ירה בים. In our case the root of יודך is הרה. [The author quotes more examples of this kind, which I think we can skip. Ed.]

אכזרי Cruel. The י is paragogic, as in ¹⁰The י in פנימי is not of the same kind as that in אכזרי, as stated by I. E. himself (Moznaim, On the Hirek); in his commentary on Lev. 16:21, he quotes פנימי as an instance of an adjective with יו״ד להתיחס, a formative י to indicate relation. In his Safah Berurah (p. 29), however, he quotes פנימי and אכזרי as two instances of the paragogic יו״ד נוסף) י). This discrepancy seems to have its origin in the use of the word נוסף additional in two different meanings, (a) not radical but formative; (b) not essential but superfluous. פנימי inner (1 Kings 6:27).

רועי Either my shepherd, the י being the pronominal suffix, or belonging to a shepherd, the י signifying relation, as in פנימי inner (1 Kings 6:26), אכזרי cruel (13:9);¹⁵Comp. c. xiii. Note 7. for the tent of the shepherd does not remain in one place.