benignuman, yes, I could answer those three questions. We can compare “levels” – in fact, we need to in order to judge who is an authority in the first place! If you can’t comapre levels then how are you to know that someone is a godol? The fact that he is “accepted” as a godol only means that many people have judged his “level” to be that of a godol. But if you cannot compare levels, then these people have no right to accept him as a godol in the first place. And the same common sense that tells you so-and-so stands out among his peers making him an authority, tells you that certain so-and-so’s stand out even more. Or less.
Part of knowing who to follow is to know who is greater. Godol mimenu b’chochma ubaminyan is an assessment that it legitimately made. And as Rav Shach writes – if you dont know who to follow, follow whoever is greater – and, he adds, you can of course tell who is greater. If you yourself dont know, then thats fine – not everyone can know the answer to all questions they encounter – but why in the world would you say nobody else can know? And it’s an error in logic, too, because they themselves compared “levels” of other people! i.e.: “Rav Ovadia Yosef shlita is the leading Sefardi posek of our times.” And how would they know this if you cannot compare him to other sefardi poskim?
And how can one know whether “any of us are on the madreiga of assessing the ‘levels’ of other people” unless you assessed the levels of all those other people who said arent “on the “madgreigah” to do that? If i were to ask you who is greater – Rav Ovadiah or Rabi Avika — would you say you cannot compare people? Rav Ovadiah or the Rambam? Avraham Avinu? So clearly, we can compare “levels”, its just that to some, certain comparisons are “obvious” and others are not. Well, to other people, perhaps who are more knowledgable and skilled in assessing these kinds of values, other comparisons are also obvious.