I sound disingenuous? You're imposing a ridiculous standard - that D's can't credibly oppose a nomination without suggesting an alternative. More specifically an alternative that Trump would nominate. That's disingenuous. The fact that a small number of R's voted for the 2 Obama justices is irrelevant (not to mention what you're implicitly saying about the rest of the R's, who didn't vote for them). Far more relevant I would think would be the nomination you're conveniently skipping over - Garland. Did the R's name 2 judges they would vote for that Obama might reasonably nominate back then?
You are putting words in my mouth as I clearly reiterated a few times already that it is nothing more than to score rhetorical points. I am not sure where you are getting the idea that they can't credibly oppose blah blah. It is nothing more than political posturing on both sides. When you put words in my mouth that I very specifically said are incorrect then yes you are being disingenuous.
Regarding Garland they were very clear that they would not conduct bearings no matter who it was well before Garland was nominated. I am not sure what you want from that. They are not saying that Garland would end the world like the dems are saying now. Was their reasoning insincere? Of course. I quoted the Barone rule about it numerous times right here on DDF.