The movie comes closest to acknowledging Sinclair's previous career when Clancy, hoping to diffuse Doc's sudden romantic attentions, casually states that she likes men only "two at a time." Though the line comes from Pynchon's novel, when delivered by Sinclair It becomes a subtle, anachronistic joke, hinting at the expansive adult-entertainment industry that would take root in LA not long after the events of Vice (set in 1970) unfold. It's one of many moments that feel characteristic of both Pynchon and Anderson. The author's novels are full of anachronistic jokes (Against the Day, for instance, takes place in the late-19th and early-20th centuries and features allusions to The Simpsons and Burger King), and Anderson, of course, is no stranger to the adult-film industry. Boogie Nights is surely the most famous mainstream movie about the making of porno films, and major characters in both Magnolia and Punch-Drunk Love trade in male sexual fantasies for profit. The impulsive horndog played by Joaquin Phoenix in The Master would probably be addicted to Internet porn if he were alive today.
Anderson, who was born in the San Fernando Valley in 1970, has been aware of the porn industry since grade school. On a recent episode of Marc Maron's WTF podcast, the writer-director recalls a mysterious house that sat across the street from where his grandmother lived when he was a kid—she suspected it was being used as a set for dirty movies. This seems to have been a formative experience for Anderson. He started researching the history of the industry by the time he was in high school and completed The Dirk Diggler Story (the short film he later expanded into Boogie Nights) when he was 18. Nearly all his movies depict commodified male sex fantasies as an established part of American culture, comparable to Hollywood movies or pop music. Consider the unemphatic manner in which Anderson introduces the phone sex service in Punch-Drunk, Phoenix's perverse longings in Master, or the Chick Planet Massage Parlor in Vice.
The director isn't unsympathetic to the women who act out these fantasies (the porn actress and trophy wife played by Julianne Moore in Boogie and Magnolia, respectively, are some of the most sympathetic characters Anderson's written), though his deepest sympathies would seem to lie with the men who devise and consume them. His protagonists, who are uniformly male, tend to be either naive loners longing for some idealized woman or power-hungry patriarchs with no compunctions about using women for sex. (The relatively asexual tycoon played by Daniel Day-Lewis in There Will Be Blood is something of an exception, though his libido seems to have been sublimated into lust for money and power.) Both types are thoroughly adolescent in their view of women. Whether they recognize it or not, they expect the women they desire to cater to their needs—the idea of a mutually enriching partnership with a woman would seem beyond their grasp. Punch-Drunk culminates with Adam Sandler's fragile sociopath pledging his love to Emily Watson, but it's worth noting that the movie gives us no idea of what their relationship will be like.
Anderson clearly regards his two male types as mirror images. The Master is all but constructed around this idea, and Inherent Vice revisits it in the friendship that develops between Phoenix's flower child and Josh Brolin's authoritarian cop. These movies take place in a world designed by and for emotionally stunted straight men, but that's not to say Anderson views this world optimistically. I'd argue that he's yet to create a genuinely heroic male protagonist (Philip Baker Hall's rueful gambler in Hard Eight does good only after a lifetime of doing wrong), and that his protagonists' undoing is often tied to their adolescent notions of sex and power. The tycoons of Magnolia, Blood, and Master might succeed in their professional ambitions, but all three abandon their humanity in the process, assuming they were at all humane at the start.
It's a sad fact that we live in a culture where regressive male fantasies do come true, and as Anderson argues in his period films, one might consider the history of American business as interchangeable with the historical development of those fantasies. I'm reminded of a passage in Pynchon's V. where one character speculates that all powerful institutions grew out of men's desire to lay as many women as possible. Throughout Pynchon's novels, the copious sex usually reflects power dynamics in the world at large, with patterns of submission and domination corresponding to those in economic, military, or social hierarchies. (It's possible that Pynchon has taken even greater inspiration from pornography than Anderson has.) There are some Pynchon characters who attempt to subvert those hierarchies, like the masochistic Brigadier Pudding in Gravity's Rainbow or the bisexual menage a trois of Against the Day. But more often those hierarchies prove indestructible, both in and out of the bedroom.
So it goes in Inherent Vice, both the book and the movie, wherein rich, conservative, older men poison the "free love" movement by exploiting it for personal satisfaction. One tragic development—peripheral in the book, but central to Anderson's film—is that Doc comes to realize he can be just as possessive and selfish as the establishment figures he claims to oppose. Sinclair's scene anticipates this revelation, as Doc, against his better judgment, starts to fall for a fascistic sex freak. The punch line of the scene has Clancy slapping Doc hard across the face to jolt him from both his laughing-gas-induced stupor and any dumb ideas that might be forming in his head. Sinclair, who wears on her sleeve her experience of catering to male sex fantasies, seems to know very well what strong effect those thoughts can have on men. Like Amy Adams's character in The Master (who, in her most famous scene, asserts her authority over her husband by masturbating him), Sinclair's Clancy demonstrates how women, who are less susceptible to those thoughts than men, are better capable of seeing through them. I admit that's a small consolation in a male-dominated world, though I suspect that Anderson would too.