The problem of "form" in art, especially in works of literature, disappears fairly quickly if we simply accept John Dewey's definition:
. . .form is not found exclusively in objects labeled works of art. Wherever perception has not been blunted and perverted, there is an inevitable tendency to arrange events and objects with reference to the demands of complete and unified experience. Form is a character of every experience that is an experience. Art in its specific sense enacts more deliberately and fully the conditions that effect this unity. Form may then be defined as the operation of forces that carry the experience of an event, object, scene, and situation to its own integral fulfillment. (Art as Experiemce, 137)
Thus it is quite impossible for "substance" to precede form. All experiences are given substance by their unfolding and consummation into form, as perception itself (when it hasn't been "perverted") naturally seeks form ("a complete and unified experience"). Art makes the human form-imposing impulse itself into a subject of contemplation. Thus in experiencing a work of art we are both witnessing an "event" brought "to its own integral fulfillment" and are invited to reflect on our own "inevitable tendency" to seek such fulfillment.
For me, this is one of the most important tasks undertaken by works of art, especially works of literature. I would even say that it is a process, fundamental to the way that art works, that also has "real world" implications, a carryover from literature to life, the sort of thing I otherwise often decry on this blog when discussing attempts to make literature "relevant" to life. By encouraging us to occupy the second-order level of reflection on the manifestation of form, literary art reveals our predisposition to form, at the same it satisfies it in a particularly concentrated way. (In Dewey's formulation, it "clarifies" experience by allowing us to more fully realize what it's like for a "event, object, scene and situation" to be brought to "integral fulfillment.") Literature in particular also forces a recognition of the "formal" elements of language, the way language when arranged into complex written compositions becomes ever less transparent in its capacity to "mean," ever more mediated by the form of its arrangement.
By alerting us to the ubiquity and mutability of form, art also alerts us to our attempts to impose form on life, where it is often much less benign in its its effect, much more likely to close off experience than to enhance it. (This is my own further amplification of the implications of Dewey's thought, not something he himself says in so many words.)
At the same time, Dewey does not want us to understand artistic form as something conventional or predetermined. Indeed:
A rigid predetermination of an end-product whether by artist or beholder leads to the turning out of a mechanical or academic product. . . A statement that an artist does not care how his work eventuates would not be literally true. But it is true that he cares about the end-result as a completion of what goes before and not because of its conformity or lack of conformity with a ready-made antecedent scheme. He is willing to leave the outcome to the adequacy of the means from which it issues and which it sums up. (138)
The consummatory phase of experience--which is intervening as well as final--always presents something new. Admiration always includes an element of wonder. As a Renascence writer said: "There is no excellent beauty that hath not some strangeness in the proportion". . . . (139)
In my opinion, the resistance to form in some quarters of American fiction--Kerouac, say, or Bukowski--comes from a failure to consider this aspect of aesthetic form. Form does not refer to the mindless recapitulation of strategies deemed appropriate (by whatever shadowy cabal responsible for enforcing the rules) for composing what we agree to call a "novel," a "short story," or a "poem," but to what emerges from the "adequacy of means" adopted by the artist, the "consummatory phase" that always--at least in the most admirable works of literary art--results in "something new," a something new many readers will find "strange." Form ought not be dismissed because it is upheld by the literary worlds's elitist powers-that-be but should be embraced because it so often confounds them.