Most times cracks in the gelcoat are just that, I put the Tornado pic in just to show that it doesnt hurt to have a close look at cracks. I did a repair on the kids Arrow for a small delamination when I ground back the gelcoat and followed the cracks I had to chop out about 600mm from the bottom and inner sides. How do you know how bad a crack is without grinding it? If the inner tapes intact it would still hold air.