Kacc 1-4-12 (query, "agyāgāraŋ")

Under the sub-rule to 1-4-12 (discussed by Dr. Pind in his article)

I wonder at the example agyāgāraŋ.  Is the point here that agga + ya +
agāraŋ = agyāgāraŋ (viz., agga + ya becomes agya rather than aggya)?
Vidyabhusana's "scan" of this example doesn't make much sense to me.

I'm currently translating the sub-rule as follows (subject to change):

We are to infer from [the verse's use of] "and" that [wherever] three
[consonants are adjoined] in the middle [of a word or compound,] one
of the identical pair [may be] elided, such as with: [forming a
compound word from agga + ya + agāraŋ =] agyāgāraŋ [viz., eliding one
g to avoid the triple compound ggy. Similarly, the sequence tty is
avoided by dropping one t where vutti + assa = vutyassa, as in the
phrase:] paṭisantāravutyassa.

I would also note that the main rule is not (explicitly) restricted to
identical pairs, but to any "adjoined consonants", which would seem to
me to include, e.g., "ddh" and "kkh" (viz., not exclusively "dd",
"kk", etc.) --although the later layers of the text do not flesh out
this possibility left open by the rule.