Within his commentary on PMS 1.1.5, Veṅkaṭanātha discusses conflicts among different sources of linguistic communication, e.g., the Vedas and the Buddhist canon, or the Vedas and the Dharmaśāstras.

The second way is much trickier, because since the time of Kumārila every Mīmāṃsaka agrees that recollected texts such as Dharmaśāstras are also based on the Veda. Hence, how is contradiction at all possible? And, if there is any, how to deal with it?

The subcommentary by Uttamur T. Vīrarāghavācārya is worth quoting extensively:

Recollected texts and directly heard sacred text are either about something to be done or about a state of affairs (tattva). In the first case,
one experiences here and there an option among actions due to a specific sacred text and a specific recollected text [prescribing two different courses of actions].
Then, there is indeed option [between the contradictory commands], because one postulates (sambhū-) also a sacred text being the root for the recollected text which points to actions contradicting the available sacred text (so that the contradiction is no longer between an available sacred text and a recollected one, but between two sacred texts).

smṛtyāgamayor […] kāryaviṣayakatvaṃ vā, tattvaviṣayakatvaṃ vā. ādye, kriyāvikalpasya śrutibhedena smṛ[ti]bhedena ca tatra tatra darśanāt pratyakṣaśrutiviruddhakriyāparasmṛtimūlabhūtaśruter api sambhāvitatvāt vikalpa eva.

I should add that only the first case (ādya) is addressed, because so does the main text (the Seśvaramīmāṃsā). Anyway, the concluding line is more complicated:

But, since on an optional matter one handles as one wishes, they prefer only the sacred text which is presently available —this [approach] is different than that.

paraṃ vikalpitasthale yathāruci anuṣṭhānāt pratyakṣaśrutam eva rocayanta ity anyad etat.

Now, a couple of things puzzle me here. First, what is the causal connection between the first clause and the second one? Why is it that if one handles as one wishes, one prefers the directly available sacred text? Second, what it meant by anyad etat?

Do readers have any suggestion?