Just to take on [1], the difference between computer science papers and the postmodern papers that involve physics is that while both may seem unintelligible to someone unskilled in the field, real computer science papers actually mean something if you know the terminology. Whenever postmodernists venture into areas where scientists can competently evaluate what they're talking about, the verdict is that they spew absolute rubbish, so it should make us think hard about whether any of the other stuff makes any more sense than it appears to.
It's not proof that the whole field is garbage by any means, but it is at least clear evidence that a lot of respected names in the field are publishing crap that they provably don't understand. That's really not a good sign - there may be crap published in fields like physics, but it's not coming from the Feynmans, it's coming from the relative unknowns.
There are two aspects to this. Firstly, postmodernism hardly concerns itself with venturing into scientific arenas at all. The endeavors which Sokal et al. deride are not representative of postmodernism as a whole.
Secondly, while I haven't read the papers from which Sokal et al. take their examples, and don't know what they were about, I am certain that they're not trying to contribute to scientific knowledge in any conventional sense. I gather from a friend who studies this stuff that Irigaray was playing with the language of scientific discourse in some way. I haven't looked into it further. Some of the stuff Sokal derides certainly deserves it. One of his examples is where Irigaray's work is used to justify sloppy thinking about feminism in science education. That is definitely problematic and deserves to be dismissed out of hand. But generally speaking, Sokal picked out these quotes without clearly explaining their context and intent, and that seems problematic, too.
It's not proof that the whole field is garbage by any means, but it is at least clear evidence that a lot of respected names in the field are publishing crap that they provably don't understand. That's really not a good sign - there may be crap published in fields like physics, but it's not coming from the Feynmans, it's coming from the relative unknowns.