You mention the symptom is you can sheet block to block, and never were able to do that before. This does not mean hulls are shot. There are others causes that can create this effect. Are you sure you set up the mast with the forestay position the same place on the bridle as always? If you didn't, your mast would be "raked" farther aft, and you would experience the same symptoms. Also, check the forestay and bridle wires theoretically, the nicropress fittings could start slipping prior to catastrophic failure. I would check items like these before you get depressed about your hulls.



Now about the NACRA hulls - pre-foam, with internal stringers. They can get soft eventually, and there was a real good thread a few months back about how to detect it, and how to fix it. Search for "soft spot" and "hull delamination", also on the Hobie forum.

I'm sure others will chime in with more direct links.