In order to reduce the strain on the tubing and transfer some of the load back to the hull skin, would it be possible to create one or two 'bridges' down each groove? You would have to create an additional opening to feed the trampoline and have appropriate breaks in the boltrope. Additionally, if required you could also reinforce the inboard part of the groove on the outer surface by laminating with unidirectional carbon and epoxy. This could be faired in and painted but shouldn't be too obtrusive as it would be hidden by the trampoline.

Cheshirecatman