I've got a wing (Cabrinha Mantis)that is Blown out(Back half near trailing edge is pretty bagged)

Has anyone had luck re-cutting a wing to take up the slack in the canopy to give it a 2nd life?

I'be not tried but I did discuss this with our local kite/wind repair guy.
He said it's not worth it, use it till it's dead. He said the time and effort recutting and restitching is significant and it's very difficult to get the shape right. It wouldn't be too long before it'd be in the bin and a new one in the car.