One wonders here why the repeated so in the first part of the verse is not found in the second part; that is, we have “so exquisite and so bitter” versus “so exquisite and sweet”. The original manuscript is basically extant for this whole passage; the so definitely appears before bitter but not before sweet. In theory, there are two possibilities for error: an extra so was added in the first case or the so was omitted in the second case. The error, if there is one, would have occurred as Joseph Smith dictated the text to Oliver Cowdery.
Internal evidence definitely argues that if there is an error, it is the repeated so in the first
case, “so exquisite and so bitter”. Elsewhere in the text, when simple adjectives are conjoined, the so is never repeated (I include here the second case from Alma 36:21):
There are also nonrepeating instances of “so ” where simple nouns are conjoined:
Elsewhere there are examples of the repeated so, but only in more complex conjuncts involving the repetition of “so ”:
We note that two of these examples (Alma 62:35 and Ether 14:21) include instances of simple conjuncts of adjectives or nouns where, as we have seen, the so is not repeated.
If the extra so in “so exquisite and so bitter” is an early error in the text, one wonders how it could have been introduced. There are no nearby instances of the repeated so that could have reasonably prompted such an error (the nearest preceding instance, “so much light and so much knowledge”, is in Alma 9:19). And the following nonrepeating “so exquisite and sweet” in this verse could not have caused the repetition of the so. These considerations argue that the use of the repeated so in “so exquisite and so bitter” must be intended, despite its exceptionality. The critical text will therefore maintain the variability in Alma 36:21, with one instance of repeated so (“so exquisite and so bitter”) and one of nonrepeated so (“so exquisite and sweet”).
The King James Bible has only one example of the repeated so with adjectival conjuncts. In this case, two verbless predicates are conjoined:
There are no examples in the King James text itself of the nonrepeated so. Interestingly, however, there is an example of nonrepeated so for conjoined adjectives in the dedication that the 1611 translators wrote to the king: “that … it may receive approbation and patronage from so learned and judicious a Prince as Your Highness is”.
Summary: Retain in Alma 36:21 the earliest text (the reading in 𝓞) with its repeated so in “so exquisite and so bitter” but its nonrepeated so in the parallel “so exquisite and sweet”; in this case, the instance of repetition is exceptional for the text but nonetheless appears to be intended.