Nice summation of the dative, by the way.
The long and the short of it is; I canâ€™t see how oi( in line 195 can be a dative of (dis)advantage nor an ethical dative.
What I meant by
If oi( is a dative of disadvantage then 'his' is not in the text but is assumed.
is; I took oi( as a datie of possession so that is why I translated it with 'his.' If it is actually a dative of advantage then oi( would be something like 'the armour was laying on the ground for him.'
From Monro: "The so-called dativus commodi, 'ethical dative,' &c, need not be separated from the general usage. Note however that -- The Dative of the Personal Pronoun is very often used where we should have a Possessive agreeing with a Noun in the clause."
From Goodwin's "Greek Grammar" (1170), under the discussion of "dative of advantage or disadvantage: "Sometimes this dative has a force which seems to approach that of a possessive genitive."
Similarly in Smyth, ktl.
I realize that you know all this. I share your frustration with the haziness of this typology of the dative (and other cases). But it is good to remember that these categories are the inventions of grammarians. A\ propos, here is Leonard Palmer: "The categories to which grammarians affix their various labels are nothing more than associational groups or 'fairy rings' into which words naturally fall in virtue of their meaning."
I think it's safe to say that the dative in our example connotes neither location, nor instrument. Hence it belongs to that larger 'fairy ring' called the 'true dative' comprising dative of the indirect object, dative of (dis)advantage, ethical dative, dative of possession, ktl.
I am not convinced that one need know much more than this. Context matters.