I think I've just learned to ignore it when the band starts in on the discordant-guitar-screeching. There's a lot to like with Wilco, but they do seem to like to "deconstruct" once in a while, and I just don't enjoy that part of it.
Yeah, that's some of my favorite aspects of their music. I can hear pretty ditties from any number of bands, but they're so good at taking their own material and as Tweedy has said, "destroying it." It's artfully done and is much more difficult than it seems. [edit] -this is not to say that they don't have "pretty ditties," as you know, they absolutely do. I think Nels Cline is the greatest: That solo is all over the place and ends up in some screechy, discordant places but it's just one hell of a journey. Then there are moments like the ones in Via Chicago -especially live, that are definitely "discordant," but I fucking love it. Bottom line is that they have such a wealth of material at this point that to dismiss them as "this" or "that" just doesn't work. I for one love it all, but I'm glad you've found some of it that speaks to you, that's awesome.