Avira, I am not familiar well with frankel to argue here and not planning to. You have a good point on difference between people who can argue with each other and explore their positions v. later readers. On the other hand, later readers have a benefit of seeing a full picture of opinions, while a particular person inside the argument does not. So, if someone can look at all opinions of a particular Rav and find a pattern in his opinions, then it might be a valid pattern.
but we sidetracked. To clarify my original question – do we have commentators who comment on related sugyot but do not validate unicorns? Then, maybe they are not unicorn-supporters.