It is a Hollywood maxim that a knockout display of knockers is the ultimate trump card on the red carpet. No flash of flesh is surer to send tongues wagging or leave people speechless, and Sarah Silverman’s dramatic décolletage Wednesday night is the ultimate proof.

Walking the red carpet for the Los Angeles premiere of her new movie I Smile Back, Silverman wore a black fitted bodice dress with, the pièce de résistance, a neckline that plunged deeper than Niagara Falls.

“Jaw-dropping” hailed both People and MailOnline at Silverman’s delicious cleavage.

The comedian and actress has earned almost universal praise for the boob-displaying ensemble. The MailOnline and other sites offered extra—and somewhat patronizing—snaps to Silverman pulling off the look at age 44 (because Hollywood has an absurdly short shelf life for female sexiness).

A day prior to Silverman’s red carpet appearance, Beyoncé was also earning headlines for her breast-baring maroon gown—though not as much for fashion accolades.

A nervous assistant anxiously tried to readjust Beyoncé’s dress to make sure the cleavage was just right, only to be shooed away by Sasha Fierce with a clear “Stop it.” Poor thing. Didn’t she realize that Queen Bey’s boobs are always perfect?

Still, it’s easy to understand why that hapless (and, perhaps, unemployed?) assistant was anxious around Beyoncé’s boobs.

Cleavage and the red carpet can be a recipe for success, but just as easily one for disaster. Why do we gush over Silverman’s décolletage but cringe a bit when look back at the sky-high cleavage Pamela Anderson rocked—hell, made a career out of—in the 1990s?

“Fashion has changed the way cleavage is displayed,” Elisabeth Dale, breast expert and author of bOObs: A Guide to Your Girls, told The Daily Beast.

“The more popular cleavage in the late 1990s was to have it pushed up to your neck, the tits-on-a-platter,” Dale said. “The new kind of cleavage is the deep V-neck with the breasts more in a tear-drop shape.”

The focus on the V-neck plunging cleavage as opposed to the squeezed together, overflowing bosom speaks to a shift away from the heavily contrived, almost artificial look of breasts, according to Dale.

In contrast to the former red carpet trend that was about the “Victoria’s Secret push-up bra look,” the goal now is to “show off, as if to say ‘Oh, I’m not wearing a bra,’” Dale said.

It’s no secret that there’s been a move both in the world of fashion and among celebrities to ditch the bra (and this writer has eagerly championed the movement).

Silverman’s V-neck cleavage is part of the growing ideal of the “natural” breast look.

“I think in a cleavage-baring dress, it’s important to make sure your breasts look natural, Sara Paulsen, a stylist who has done red carpet looks for celebrities like Mindy Kaling, told The Daily Beast.

“I think we’re getting to the place where the natural boob is really the sexiest. Even if a woman gets a boob job done, I like if it sags a little bit because nothing is natural about cleavage to the neck. That’s when it’s out of control.”

Dr. Oren Tepper, a plastic surgeon in New York, confirmed that more women are seeking the “natural” look—though this has been a more general trend in plastic surgery. “The desire for the unoperated natural look, we’ve already seen it with faces and noses. With breasts, it’s the last loop to be closed.”

Of course, the irony of wanting the more natural look of looser cleavage is that it can actually take quite a bit of smoke and mirrors to create the look of apparently effortless décolletage.

“Cleavage is man-made,” said Dale. “If you’re sitting there without a bra and your boobs are hanging out, they’d never just look like that.”

While Silverman’s press rep did not return our query about the dress design by the time of publication, both Paulsen and Dale suspected there were cups or underwiring in the dress.

“Her breasts look very round and circular. She’s definitely lifted and taped in,” said Dale. But all the more power to her, she added. “She looks great. Her boobs are in great shape. I’m 59, and my tits are down to my knees. In 10 years, she won’t be able to wear this.”

Paulsen said she knows of women who use duct tape to help their breasts fight gravity in plunging necklines. For those of us who, understandably, don’t want duct tape gracing our nipples, she recommends special breast lifting tape and side cups.

However, there was more to the success of Silverman’s red carpet look than some careful cleavage shaping, said Paulsen.

“With something this dramatic, I really think you need to choose one erogenous zone. It’s not also showing the butt or too much skin,” said Paulsen. “Also, it’s black, so it’s not ‘Hello, look at me.’ It’s very chic and not overstated.”

And while breasts may be the most ooo’d and ahh’d over part of the female anatomy, those of us who possess them know that they have the potential to work against us.

Perhaps the one cleavage consistency that transcends time is that “there is still a judgment made, whether it’s good or bad,” said Dale.

Dale has her own guidelines for women to navigate that judgment. One of her main rules is “if cleavage isn’t in your job description, don’t write it in,” which is to say, unless your job is to walk red carpets and look sexy, maybe keep the boobs out of the offices.

She even ventured that such a display of cleavage would have hindered Silverman during her stand-up.

“If she wore something like this while she was on the stage, the audience would just be staring at her tits,” said Dale. “We don’t focus on how breasts can be a source of attraction and distraction at the same time.”

That’s the line women walk when it comes to the agony and ecstasy of cleavage. And while displays of décolletage may change, it’s as certain as death and taxes that we will still be talking and thinking about them.

“Breasts never get old,” said Dale. “No one is ever tired of seeing boobs.”