Some additional points:
The other instances of prophecy (the primary practice associated with seiðr), Oðinn is not the one prophesying. In Baldrs draumar, he raised up a dead witch in the underworld to tell him what he needed to know.
The instances of prophecy as mentioned in Ynglinga saga 7 are of an euhemerized version of him, and therefore should be looked at with some scrutiny. The saga gives a specific overview of what these different practices and types of magic are, but his association is primarily with galdr, shapeshifting, weather/element manipulation, battle-sorcery, herb-magic, and knowing the language of birds. Some of the practices such as shapeshifting are reminiscent of the Sámi Noadi practices. They are also said to be able to send out their spirit in the forms of animals while their bodies are sleeping.
In the instance of his impregnation of Rindr, Sigurðardrápa denotes this was accomplished by seiðr (seið Yggr til Rindar), but in Grógaldr it is denoted as galdr (þann gól Rindi Rani).
The accusation of the Samsø episode in Lokasenna in my view is really just that, an accusation, which is the premise of the senna style poetic form. Óðinn here is said to have used a drum like völva. He was said to have vitka líki fórtu verþjóð yfir, or have fared in the likeness of a warlock over men. The term vitka used has a connotation of controlling the senses, such as in vitkask, which refers to the recovering of one’s senses, or recovering from being in a swoon. The term vitka is associated with Finns (finnvitka, meaning to bewitch like a Finn), as they (or their mixed descendants) are typically the purveyors of sorcery in the sagas. In this lost story, it’s likely that Óðinn had used sorcery to control the senses of the men on Samsø.
My personal view on the matter is that Óðinn being a god, is not subject to the moralities of men. When in preparation for the Ragnarok, he must do what must be done and use every potential resource possible.
