Lacan saw both language and the primary process of the unconscious as mainly governed by Jakobsonian metaphor and metonymy. While especially well adapted to accounting for poetry, word salads, and dreams, the Jakobsonian approach seems insufficiently constrained to be able to account for proprieties of inference; but then, it was not developed for that purpose. (See also Imaginary, Symbolic, Real.)
Brandom sees any descriptive, formal view of language such as the Jakobsonian one as ultimately parasitic on a nonformal, normative, and material-inferential view. For rational, discursive purposes where we want deontic modal constraints, Brandom’s approach works very well. Brandom’s account focuses on the normative and inferential meaning of ordinary empirical concepts, and has nothing to say about free metaphor and metonymy, which also have a big place in the wider world; but then, it was not developed for the latter purpose.
I don’t mean to suggest any facile symmetry here, just the bare possibility of some reconciliation in view of the fact that the main concerns of the two approaches are mutually exclusive. Saying that a view is parasitic on another view is very different from saying it is wrong. The question is whether it is fair to expect that Brandom’s claim of parasitism at a general level of formal on “material” and of descriptive on normative approaches imposes on Brandom an obligation to be able to explain any possible formal account in his terms, including one mainly designed for a case well outside his focus. I think it does impose on him an obligation to be able to explain any formal account addressing the scope of determination of empirical concepts, but does not impose an obligation to be able to explain something like metaphor and metonymy. So, at least in this measure I do think the perspectives can coexist.
In my youth when I was a linguistically experimental poet among other things, I put more stress on metaphor and metonymy myself. At that point, I still believed in rational intuition, did not really think of reasoning in terms of language, and was even a bit disdainful of breaking things down into steps. Now I think all intuition is secondary to some prior development. As soon as I encountered Brandom’s argument about the priority of inference over representation, it seemed very right, and I began to engage with other aspects of his work from there. We could squint and say metaphor and metonymy are forms of representation, but if so it is certainly not empirical conceptual representation, so I’m inclined to think in that case we’re dealing with an Aristotelian homonym.