Strumming an acoustic guitar, Paltrow gave the audience a taste of "Country Strong," the title song from her upcoming movie, scheduled for release in January. The film is about a country-music singer – in need of a comeback – who hooks up with a songwriter (Garrett Hedlund) on his way up.
Not surprisingly, Paltrow's appearance on the CMA stage – her acting credits include an Oscar-winning turn in "Shakespeare in Love," a side-kick role in the "Iron Man" movies, and an appearance on "Glee" next week – fueled comments.
One post on The Wall Street Journal's "Speakeasy" column said, "Hard to go wrong when you have Vince Gill singing harmony with you. Good job!" Another wrote, "I actually had to change the channel during her performance."
Even though Paltrow has sung on film before – she and Huey Lewis sang together in "Duets" a decade ago – some viewers probably wondered whether Paltrow's musician husband – Chris Martin, who fronts the British music group Coldplay – had something to do with her transformation.
But others may have more correctly asked whether the phenomenon – of actresses breaking into song – is about nature vs. nurture.
In other words, do talented actress-singers – Reese Witherspoon in "Walk the Line," Meryl Streep in "Mamma Mia," Kate Hudson in "Nine," and others – owe it all to innate singing ability or good coaching?
The answer, say the experts, may be a little of both.
"Actresses in general have no guaranteed advantage over anyone else when it comes to being a good singer," said Roger Love, a veteran vocal coach in Hollywood. Love worked with Jeff Bridges, whose portrayal of a washed-up country-western singer in "Crazy Heart" won him an Oscar.
For Love, one factor that allows an actress to become a successful actress-singer is a musicality that has impelled her to sing – informally and often – in her private life, over many years. "Singing along to recorded vocal music is like having a mini-singing lesson," he said.
"I could tell from Gwyneth Paltrow's CMA performance that she's obviously a person who grew up exposed to music and enjoyed her own private time singing," he said. "I could hear from her pitch and rhythm that she has a history of putting her voice close enough to where it's supposed to go."
Love concedes that some people's vocal apparatus is simply better than others, which makes for a speaking voice that's pleasing as opposed to, say, nasal or bass-like.
Does that translate into a short coaching period before she can hit the recording studio?
If the actress has a considerable amount of non-professional singing time under her belt, Love said, it's often just a matter of teaching her vocal and breathing techniques to go along with her natural talent. He's very lucky if movie studios allow him a couple of months to accomplish this, he said.
"But all I needed to do when I coached Reese" – Reese Witherspoon, who received an Oscar for her portrayal of June Carter in "Walk the Line" – "was to give her enough vocal technique which allowed her to incorporate her acting talent into the singing," said Love.
But not every actress can make acting an integral part of the musical performance.
"Actresses who sing often make 'small' acting choices, which unfortunately tend to get swallowed up by the music," said Love. "The result is the acting doesn't come through to the audience."
Fortunately, there's a remedy.
"Fearlessness – not the reckless kind but the sort of push that inspires – helps a lot," said Deborah Lapidus, a teacher of singing and song performance at both Juilliard and Tisch School of the Arts at New York University. "Fear impedes the ability to sing well.
"Certain actresses are so self-conscious about singing that they edit themselves even before opening their mouths, which causes their entire body to constrict," said Lapidus, who also coaches privately and has worked with Sigourney Weaver, Claire Danes and Debra Messing.
"When an actress's body is relaxed and well-supported by proper breathing, it allows her to be more expressive and melodic in speaking and in singing, which you can hear in actresses, such as Meryl Streep," she said. "The goal is for the acting and singing to become one experience."
And the actress-singers who manage that are the ones who get the most kudos.
"It's about expectations," said Lapidus. "If a performer is primarily a singer, like Beyonce, we have high expectations. But if we see an actress – that we never thought of as a chanteuse – sing well, we're pleasantly surprised because our expectations weren't high to begin with."