This morning's driving music (I don't usually drive into town, so when I do, I choose my music carefully) was Brahms 3, which is slowly but surely supplanting 2 as my favorite Brahms symphony. It's among a small group of Brahms pieces that don't feel like they've been planned so meticulously; if I don't listen too closely, there are things happening that sound like they're in there not because they develop a motive, or set up a new theme, or make some structural point, but just because Johannes damn well felt like it.
It's an illusion, of course—it's as tightly constructed as anything else he wrote—but it manages to nail that simulated spontaneity that composers are encouraged to strive for in their academic training. Sound fresh and surprising, but using material that's developed organically. I suppose it's natural for that to be a teaching aim; practice grows out of analysis, and to teach analysis, you need music where it's easy and logical to demonstrate where the notes are coming from. (Over on his blog, Kyle Gann had a great post on this topic a couple of weeks ago.) A lot of composers react to this sort of training by going to the other extreme: music that refuses to develop, themes following themes with no transition, relying on the drama of juxtaposition to carry the piece forward. (I often like music like this—Feldman and Zorn spring to mind as varied examples—but I do think it's much harder to pull off.)
But then I started to try and imagine a piece that's an illusion in the opposite direction: a hodge-podge that fools you into thinking it's tightly, organically constructed. My favorite example of this is Tosca. Think of the very beginning, those three big chords:
Which is immediately and suddenly followed by all this activity:
So we have a bunch of harmonies with no functional relationship to each other, and a couple of diametrically opposed tempi jammed together with a fermata. With your ear thus primed, Puccini is now free to go to any harmony or tempo he wants without the need to modulate. And in this context, paradoxically, the lack of modulation makes the piece sound more like everything's connected. There's no long transitions, no musical gymnastics to get from place to place; he just does a sudden bump change and your brain subconsciously says, "Aha! Just like the beginning." Then, without any preparation, he just brings back the three big chords at the act breaks, and you're suckered into thinking that there's a grand structure unfolding, when in fact, the only real planning he's doing is saving a couple of tonalities for big arias.
Please note that I don't think this is in any way dishonest or underhanded on Puccini's part; I actually think it's an extremely clever way to maintain the speed and dash he wants without being tied down to musical niceties. (Charles Rosen offers a similar compliment to Mendelssohn in The Romantic Generation regarding a "fugue" with no counterpoint.) I do wonder how often one could get away with it—you get the feeling that Puccini is trying the same thing at the opening of Turandot but then realizes that it's unsuited to the grandeur and spectacle of the story. And I can't for the life of me imagine how to do something similar with serial music, which is (at least analytically) organic by definition: everything springs from the same sequence of intervals. Maybe Tosca really is an organically developing piece, but the generating source is just the sounds of triadic tonality, an idea so far in the background that we take it for granted.
Something I've been trying in my own music for a couple of years now is applying serial techniques to groups of triadic harmonies: for example, devise a tone row that divides up into triads and seventh chords, and then put those chords front and center, voicing and doubling like you normally would. I like the sound world that results—because my ears are tuned to tonal progressions, the sequences sound simultaneously familiar and surprising. The harmonies don't go where they "should," but they're still moving in consistent ways (thanks to the row) and that seems to hold the piece together. I suppose you could pretty easily use something like this to set up more arbitrary progressions á la Puccini, but the effect would still be based on that tonal ground. Odd—I'm used to hearing atonal music criticized as a violation of musical grammar, but here's an instance where it's actually too grammatical.