Sam I dont see why you ever have to think a rishon or acharon is (completely!) wrong (though i see it done sometimes by emmese poskim (quite often with apparent hesitation and respect) but its not a proof for anybody else, even talmidei chachomim) you can always instead say i dont understand (that doesnt mean they are right though, they might be wrong) what hes saying and leave it at that without implying right or wrong and still follow your own line of thinking (unless you are being don din liatzmo (where in addition to other factors there is a hisarvus of pniyos and adam korov eitzel atzmo)). It makes a difference because first of all its quite likely that you are mistaken (kinire bchush) and its obviously important to give somebody who is much smarter and more knowledgeable than you especially when they took the effort of trying to be asuki shmaata aliba dihilchisa and obviously made thorough research as much as they could possibly do, because of their daiga of not being mateh the rabim the benefit of the doubt. Since that happens to be the case it also has the quality of anivus and bittul and somebody who doesnt think that way is not makir mikomo (and mikom hagdolim) and is a baal gaavah. If it seems to be an obvious and inconsequential distinction know that its actually very significant, because even if you would somehow taaneh either way is a true way to look at it, the fact is, we are talking about talmidei chachomim here who you have to approach with kovod, therefore surely in your speech and even in your thoughts this is the right approach.
In your most recent post you even seem to backtrack a little yet you still said what you said in previous post.