Tedder has spent years crafting hits for the likes of Madonna, Beyonce, Adele, Kelly Clarkson, Jennifer Lopez, U2, and Maroon 5, but he admits the Shake It Off singer really blew him away with her sheer talent and professionalism.
"Taylor brings more overall skill sets to a writing session than anyone I've ever worked with," Ryan gushed on U.S. breakfast show Today, after helping Taylor pen the tracks I Know Places and Welcome to New York, from her 1989 release.
"She's a machine, in the best way possible. She has an idea of the song she wants to do the night before, you walk in, sit down, 'Hey, how's it going? Alright, let's go.'"
Ryan goes on to reveal Taylor knows "in her DNA" if a track will be a hit, and she has no problem completing a whole tune in just one session.
He added, "Whatever I took in (about what makes a hit) over decades of listening to music is what I put out, and Taylor's the same way, but she walks in and just bangs out a song, top down, and you walk out with a finished record, which is very rare."
Tedder claims working with Swift is very different from collaborating with fellow powerhouses Beyonce or Adele, because they like to focus first on the song words, before getting the music down.
"Beyonce is super lyrics intensive, you can tell by her last couple records, so if the lyric isn't her life, she's off it," he continued. "Adele, same way."
And he insists if the British soul sensation ever wanted to give up the singing side of her career, she'd have no problem earning a living writing for other artists.
"If she wasn't Adele the singer, she'd be Adele the songwriter," he claimed. "She'd be one of the best writers in the world."
Tedder co-wrote Beyonce's XO from her self-titled 2013 release, and contributed to Adele's tracks Remedy from 25 and Rumour Has It and Turning Tables from 21.