I've never broken a skeg, but operating in all this sand and ground shells out here, I can sure wear them down a nub in no time. Whenever that happens, I just take a circular saw and cut it off straight, then cut a new triangle-shaped piece of 1/4 aluminum plate, bevel both sides of the seam, and weld it on there at about 150 amps.
It's important to have that skeg, as this is what hits bottom/obstructions before your prop. Without it, the prop blades will hit, and you'll damage your prop. I've seen quite a few people running their boat with broken off skegs, and a large percentage of those people have prop blades that are so bent, they look more like blender blades. :shock: