A film should be self-explanatory. I recall watching a Pasolini film once that was annotated (sort of footnotes during the end credits, listing sources for the viewer to go to after leaving the theater, that were relevant to the maestro's creation). But in general, what you see is what you get, and a film-goer should be expected to have enough intelligence to watch without Cliff Notes.
But a generation of vidiots has become attuned, almost in Pavlovian fashion, to expecting and then ingesting the modern equivalent of the advertising featurettes that were made by Hollywood to promote its pictures in the pre-Video Era.
This one about LARS is strictly of the rah-rah variety. The talented screenwriter almost facetiously talks of how she found the "naughty" sex doll website while surfing on the web during one of her odd jobs (she's a poster child for DO quit your day job, and pursue something risky like scripting in the movie biz instead).
The director is not very interesting -his career credits indicate little ambition beyond hackwork, though LARS is clearly an exception. There's a truly token 3-minute contribution to the much-beloved (I hate it!) "Deleted Scenes" slot, where we see Ryan get into the bathtub with his doll, the bubbles covering her breasts so as not to offend anybody. That's typical of the film's overly-teasing & and lack of guts approach to its underlying motif -the not-shown image of a guy humping one of the "realistic" (also not shown) orifices of a plastic doll.
The director hated to lose this brief segment, but in the DVD era gets to have it both ways -we see it anyway. Why not stick it back in the film (in sequence) and bamboozle the public with a DVD trumpeted as "Special Edition -Director's Cut", merely 3 minutes longer than the real, theatrical release? The suckers out there would eat that up, too.
This missing scene unveils a key element omitted from the finished film: the issue of sexuality. Apart from a brief bad-joke scene of girls chatting about the anatomical correctness of Bionca, the sex doll's erotic status is sidestepped and the filmmakers do not discuss this, even though the website's hint/hint, nudge/nudge promotion of the toys is all about masturbation.
That brings up the key failing of the film, and the most basic decision made at both scripting and shooting stages, also not discussed here at all. In previous treatments of the subject, notably Arne Mattsson's THE DOLL (store mannequin), LIVING DOLL (a morbid British horror video stressing black humor about a corpse) and Joe Sarno's PARTY DOLL (Ron Jeremy in love with a sex toy), a far more cinematic approach is adopted. The earlier films & videos have the corpse or doll coming to life, as seen from the male protagonist's point-of-view. Here, they decided Lars would talk to the doll but Bionca remains inanimate for the duration -a minimalist approach that I found ultimately self-defeating.
This is the equivalent of making any of the umpteen versions of HEAVEN CAN WAIT realistically rather than using the powers of cinema. A specific example would be the Warren Beatty version, where very early in the narrative the character Beatty plays dies and is replaced by the old guy whose body he subsequently inhabits. A "Lars" style would limit that fantasy film to depicting for next hour-plus the old guy, since that is what everyone else sees, including even Beatty looking in a mirror. Instead, because he is the star and in effect the film's raison d'etre, we see Beatty's body throughout, representing visually his living personality (in the unseen body of another). By eschewing fantasy AND sexuality the LARS people leave everything to one's imagination and have created a work more suitable to radio than cinema.
The cast has the usual interview love-fest, giving us a chance to see one of the inevitable imported stars, in this case Emily Mortimer (often it's just good old Christian Bale), talking with her REAL accent. Ryan appears to be speaking tongue-in-cheek about his "naughty" over-attachment to Bionca the doll.
Sum total of content here is identical to thousands of other DVD promos: another brilliant film was made and the makers couldn't be more thrilled. The only thing this sort of filler is superior to is the "do over" version of audio tracks on DVDs of films that bombed: I recall listening to a most obnoxious Gillian Armstrong voice-over commentary for one of her flops where she spends two hours alibi-ing and complaining, almost scene for scene, how the critics "just didn't get it". Even Terry Gilliam, usually a funny guy whom I once had the pleasure (30 years ago for TIME BANDITS) of interviewing, spent the length of his DVD commentary for TIDELAND whining about how misunderstood the movie was.
Let's face it - the people who make movies are almost contractually compelled to sit down and crank out these stupid addenda to their work, and the public apparently eats it up. It's just part of the biz now, no different than a star being forced to sit through a round of media interviews for a couple of days on a press junket, where sleepy scribes ask the same inane questions (see: Rex Reed and "do you sleep in the nude?" for the epitome of this), to receive bored responses. It's show biz, baby.