As promised, James Cameron joined the Mythbusters guys on last night’s episode to once and for all debunk the show’s most-requested myth: The pop culture theory that Jack and Rose could’ve both survived on the plank at the end of Titanic. When Reddit explored the issue months ago, they determined that the buoyancy wasn’t enough for both bodies, which lets Rose off the hook somewhat for making Jack take to the frigid waters of the Atlantic while they waited to get rescued.

But most people wouldn’t be satisfied until Mythbusters hosts Adam Savage and Jamie Hyneman took to the plank themselves! And like I said, Cameron was a good sport about joining the experiment. Turns out Cameron gets fan e-mails every day telling him, “Rose is a selfish so-and-so [Editor's Note: we imagine there's a stronger word they use] and Jack’s an idiot.” Lo and behold, the hosts discovered that Rose and Jack could have both survived on the plank, but only under one condition. Check out this preview of them adjusting the plank to fit their actual body weight and then waiting the 63 minutes that it took for Rose to get rescued in the movie.

“Rose” and “Jack” clambered up onto the plank, and just like in the movie it started to sink. But then they had the bright idea to tie Rose’s lifejacket underneath the board! Thus giving it more buoyancy—enough that both were able to have 80% of their bodies out of the water for the full 63 minutes of waiting. That’s 100% more than Jack got. We also learned that prolonged exposure to the water slows down motor control, which is also part of why Jack drowned. But as long as they stayed on top of the board, drowning wasn’t a danger.