You cannot fully understand A Thousand Plateaus without the book that preceded it, Anti-Oedipus (1972). The earlier work has a sharper polemical edge: it is explicitly a critique of psychoanalysis, of capitalism, and of the forms of desire that both psychoanalysis and capitalism produce and reinforce.
Deleuze and Guattari's target in Anti-Oedipus is the Oedipal model of desire: the Freudian framework in which desire is fundamentally organized around the family triangle (father, mother, child), in which libidinal energy is routed through the Oedipus complex, in which subjectivity is structured by lack (you desire what you do not have). They argue that this model does two things simultaneously: it reduces the infinite productivity of desire to a narrow familial drama, and it is an ideological support for the social order by training people to desire within acceptable limits.
Their alternative: desire is not organized by lack but by production. Desire is fundamentally creative and connective, it produces assemblages, connections, new realities. As the Philosophy Now article explains, Deleuze and Guattari saw desire as "positive, a productive force within us all that should be free-flowing," not the result of lacking something but of making something. This is an extraordinarily liberatory conception of desire, and also a philosophically serious one: it connects to Spinoza's conatus, to Bergson's élan vital, to Nietzsche's will to power.
The analysis of capitalism in Anti-Oedipus is among the most original in the Marxist and post-Marxist tradition. Deleuze and Guattari argue that capitalism has a paradoxical structure: it is the most deterritorializing force in history, it constantly dissolves traditional bonds, codes, and territories in the pursuit of profit (this is basically what Marx said about the bourgeoisie melting all that is solid into air), but it simultaneously reterritorializes everything it deterritorializes, capturing the liberated flows and rechanneling them through the axiomatic of capital. Advertising, as the Philosophy Now article notes, is the paradigm case: it liberates desire from traditional constraints and then immediately recaptures it for the purpose of commodity consumption. Capitalism promises freedom and produces new, more subtle forms of capture.
This analysis has direct consequences for politics. The naive Left view, that workers are oppressed against their desire and will rebel once they understand their interests, is wrong. People often desire their own repression. Fascism was not imposed on populations that wanted freedom; people genuinely wanted fascism, in the specific sense that the desire-machines of fascist culture captured genuine libidinal energies. The political question, for Deleuze and Guattari, is not how to liberate people from external oppression but how to constitute assemblages of desire that do not turn against themselves, that pursue genuine lines of flight rather than being recaptured by the axiomatic of capital or the family or the state.
This is what schizoanalysis is: not a clinical practice but a political and analytical practice of tracing the lines of an assemblage, its molar rigidities, its molecular flexibilities, its potential lines of flight, in order to understand what kinds of desire it produces and what kinds of transformation are possible within and beyond it.