Dr. Irving Scher, a biomechanical engineer, was among the more credible folks to testify during the Gwyneth Paltrow ski trial, as he used stick figures to support her story about the collision with retired optometrist Terry Sanderson.

So, it stands to reason you’d believe his very scientific take on Betty Buzz’s Meyer lemon soda.

In a new spot from Maximum Effort, Scher once again commands the whiteboard with aplomb (actually, he seems a tad nervous, but whatever) as he explains the physics behind a person’s Betty Buzz drinking experience. And what is Scher’s expertise in this realm? Well, it says on the screen he’s a “fizzicist.”

Lively, who sets up the spot in voiceover at the very beginning, pipes up again after Scher’s brief but convincing presentation. “Case closed, Betty Buzz is probably, scientifically the best sparkling beverage in the world," she says. (To which Dr. Scher mildly objects: “I didn't necessarily say that.”)

Maximum Effort, the agency owned by Lively’s husband Ryan Reynolds, which has done a lot of the Aviation Gin advertising over the years, began doing spots for Betty Buzz about a year ago. Lively founded Betty Buzz four years ago, and it's now distributed in more than 5,000 stores across the U.S.