What makes for a believable, fake Hollywood romance? '2 willing participants and great paparazzi on speed dial,' expert says.

Taylor Swift is being accused of staging a romance with Kansas City Chiefs tight end Travis Kelce by social media users and even by public figures, including The View co-host Sara Haines, who said on Monday's edition of the show's Behind the Table podcast that she didn't want to discuss the two on the show. This comes despite Swift's very public support of Kelce at Sunday's Chiefs game, where she cheered him on from her seat — beside his mom!

"This is a PR stunt, this whole thing," Haines said, "and I'm just not that interested in it, because it feels like you're giving air to a publicity stunt."

Over at ESPN, Elle Duncan said on The Elle Duncan Show that, after seeing the two leave the stadium together, she was convinced they were "platonic."

"He's never touched that woman. They're not dating. This is a stunt," Duncan said. "Now, when I said he does not know that woman — OK, maybe he does. Apparently, he does. They're not dating."

They weren't the only ones who were suspicious.

Publicists for Swift and Kelce did not respond to Yahoo Entertainment's requests for comment.

But all the talk about a fake celebrity romance made us wonder: What does it take to produce a successful one, which has also been called a publicity stunt romance, fauxmance and even a showmance?

Hollywood honchos have concocted these kind of arrangements for as long as there's been a Hollywood. They were a way to drum up publicity around a project (say, the leading man and leading lady fall in love), the path to shifting someone's image or even a way for gay actors to hide their sexuality in a time when coming out publicly would have damaged their careers.

Celebrity publicist Liza Anderson, the owner of Los Angeles-based Anderson Group Public Relations, tells Yahoo that all such an arrangement requires is "two willing participants and great paparazzi on speed dial."

"In the beginning," Anderson says, "it was very much about the studio systems having control of their actors and making sure that they remained viable at the box office and not wanting to talk about their sexuality.... It was a horrible way to live. But I know the studios had complete control over their movie stars, and they would do it."

Anderson cited HBO's documentary Rock Hudson: All That Heaven Allowed, which explains that Hudson married his agent's secretary for this reason. Other reasons are to divert attention away from another less favorable narrative or to shake up a celeb's image.

Over the years, celebrities including Tom Cruise and Katie Holmes and Zac Efron and Vanessa Hudgens have been accused of faking romances, too, for whatever reason, and often there's no merit to these accusations. But when it comes down to it, how the parties actually feel about each other doesn't matter much: The whole point is that we're wondering.

David Schmid, an associate professor of english at the University at Buffalo who studies pop culture, says that attention is what determines whether such a pairing is successful.

"It's not defined by the couple's happiness, or the length of the relationship, but simply by whether the relationship generates attention, how much and for how long," Schmid tells Yahoo Entertainment. "In this regard, the relationship between Kim Kardashian and Pete Davidson is exemplary — a relationship patently [or] blatantly unlikely and instrumental — but very successful in provoking everyone to have an opinion about it."

PR expert Anderson notes that, in the case of Swift, her appearance at Sunday's game was effective, even if it turns out that she and Kelce didn't or don't couple up. Because of the "Anti-Hero" singer, she and a lot of others now know who Kelce is. Sales of the NFL player's jersey reportedly have increased by 400 percent and his team's ticket sales have skyrocketed since one of the world's biggest stars was seen cheering him on.

Anderson notes what a lot of Swift's fans were likely thinking too: that seeing Swift so happy was lovely.

"The whole theatrics of it all was just a wonderful thing to watch," she says of the game. "And you really are rooting for them. You really hope it's real, because they're adorable together."

The world could get another glimpse of Swelce or Traylor.

Swift reportedly plans to attend this Sunday's Chiefs game too, which the official social media accounts for Sunday Night Football on NBC seemed to play up in a teaser on Friday. The 30-second video featured Swift's song "Welcome to New York" playing behind footage of NFL players in action. The post was captioned, "Taylor Made for Sunday Night."