It's a cinematic moment that has tortured fans since tears first fell for the ill-fated lovers of the 1997 movie Titanic.

And now actress Kate Winslet​ has added to the controversy suggesting there could have been a happy ever after for Rose and Jack had the rules of film tragedy not demanded the death of one lover.

Having survived flooded cabins, and the best efforts of a jealous fiance to drown Jack, the couple plunge into the icy Atlantic Ocean from the teetering deck of the ship deemed by its makers to be unsinkable just before it cracks in two.

Leonardo DiCaprio's character Jack gives up his place on a piece of floating debris for Rose. He dies so that she might live.

Why didn't Jack just climb on the makeshift raft with Rose? Speaking on Jimmy Kimmel Live on Monday Winslet agreed.

"I think he could have actually fitted on that bit of door."

Fanatical fans have long argued the couple could have survived the wreck, even re-enacting the scene and replicating the size of the door to which Rose clung to demonstrate the door was big enough to hold two and spare them both from hypothermia.

The popular television science show Mythbusters devoted an episode to the subject. With a few tweaks to the raft by strapping life vests to the undercarriage of the door, the team concluded that it was plausible that both could have survived and Jack's death was needless.

"Actually it's not a question of room," director James Cameron once explained, "it's a question of buoyancy".

Cameron told the internet news and gaming site IGN in 2012: "When Jack puts Rose on the raft, he tries to get on the raft - he's not an idiot, he doesn't want to die - and the raft sinks; it kind of flips.'

"And so it's clear that there's really only enough buoyancy available for one person. So he makes the decision to let her be that person."

Cameron added: "If he got on with her they'd both be half in and half out of the water, and they would have both died."

The script called for Jack to die. End of story.