'If it is merely a possibility that one attending appropriately may realize the fruit of stream-entry, then there is also a possibility that he may not. And all those who do not would count as instances of puthujjanas possessed of yoniso manasikāra. Hence yoniso manasikāra may be present in a puthujjana. . . . The commentary to this sutta defines the term twice, once giving the stock commentarial definition (the paragraph beginning: "tattha _yoniso manasikāro_ nāma upāyamanasikāro...") and once a context-specific one (notice the limiting adverb "ettha", "here"). It is only in the latter that sotāpattimagga is alluded to. In the general definition there's no limiting of yoniso mansikāra to ariyans,'
which neatly contradicts your claim that yoniso manasikara is applicable only to ariya. Essentially the argument you made for the ariya only interpretation of yoniso manasikara has been shown via the commentaries and the suttas to be at best not well grounded.
I think Ven. Dhammanando may be mistaken in his interpretation of the commentarial gloss here.
Do you read the extremely difficult commentarial Pali? Ven Dhammanando, who does, might, indeed, be wrong, but given that he is highly learned in this, more so than anyone else I have seen on this forum, I rather doubt that he is wrong, and merely stating that he might be wrong is not an argument.
As for the Silavant Sutta, as I've already intimated, I'm somewhat noncommittal: it appears aberrant -- like a number of the other Suttas you've sited -- and in contradiction to other more established Suttas in the Canon.
Ah, the it-does-not-agree-with-my-point-of-view,-so-that-sutta-you-just-quoted-can-be-dismissed-as-aberrant
argument, which suggests that you, in fact, have no argument. Interestingly, you have not referenced any other "established suttas" other than Vipassi, and even that does not support your position. The suttas I quoted, and I certainly could quote any number of others, are as established as any other sutta in the Nikayas.
But as I've said, I'm open to a change of opinion. Just from my own reading of the Suttas I've always had the impression that there is an ariyan quality about the term, and I can understand how the tradition came to interpret it as such.
The problem for you here is that Ven Dhammanando has put into context what the tradition -- via the commentary you referenced -- has said, which contradicts your point of view.
It would be interesting to learn more about why Ven. Bodhi rejects the tradition here, and to gather a more compeling reason to support your view.
One comment in the commentaries is not the whole of the tradition, and Ven Dhammanando already addressed that point.