According to Sri Vaishnavism, one who has performed the Samashrayanam/Bharanyasam ritual (initiation into Pancharatra Agamas/Surrendering to Vishnu) is prohibited from worshiping Devatas like Shiva, Indra, etc. The question then becomes, how are they to avoid Devata worship when nitya and naimittika karmas like Sandhyavandanam, Agnihotra, Vedadhyayanam, Pitr worship, etc involve worship of devatas like Indra, Agni, etc.?
Two Sri Vaishnava scholars have answered this question, but differently.
Nam Pillai, who was a disciple of Parashara Bhattar, has stated this:
In the Nitya and Nimittika karmas, Srivaishnavas do worship the other deities like Indra, Varuna, Vayu, Agni etc. but there is a special rule stating that even though they worship those deities they do so not as separate entities, but as the body of Lord Sriman Narayana. Hence it is permissible and it results in the worship of Sriman Narayana only who is their inner soul.
On the other hand, Vedanta Desikan in the Rahasya Traya Sara says:
Names like Agni may be considered as directly referring to Narayana on etymological grounds. Hence, there is no worship of Devatas.
... [Or] perform these respective rites meditating that the Supreme Being has these [Devatas] as his body.
Desikan cites a reference from Ramanujacharya's Nitya:
Having pleased the gods, the rishis and the Manes with oblations and with the thought that they have Bhagavan as their inner self...
But this statement seems to me to match more closely with Nam Pillai's statements because take note of the wording of this statement: "having pleased the gods with Narayana as their self" and not "having pleased Narayana with the gods as his body".
From this it's clear that Nampillai and Ramanujacharya believe that Sri Vaishnavas are worshiping the Devatas, etc. as the body of Narayana with the thought that Narayana is their inner-self, whereas Vedanta Desikan is saying that Sri Vaishnavas should not/are not worshiping Devatas at all.
There may be some reasons for this disrepency.
Nam Pillai was born 121 years before Desikan, so maybe the Sri Vaishnava views changed by the time of Desikan.
Nam Pillai is also part of the Thenkalai branch of Sri Vaishnavism whereas Desikan is part of the Vadakalai branch, so maybe these sub-sects had differences of theory on this practice back then.
Is there any reconciliation?