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It definitely goes all the way through. I'd say put on a layer of tape and hone it out. If you round the toe a bit more, you don't have to remove steel along the whole length of the edge.

If the crack runs to the cutting edge, you should NOT shave with the razor. If the blade flexes, the crack will separate and you could get a very nasty gash.

If you could post photos, it would be...