Funny, I´m familiar with both, a crack exactly there and I´m a happy owner of a SR5006

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No cracks whatsoever on mine though! Wengue necks sound so nice...
I share Dave´s opinion out of experience. The structure is not significantly compromised.
I have a Peavey Cirrus, wallnut/maple neckthrough, that developed a crack just as yours. In my case I´d say it´s due to an excessively thin back, or saying it differently, a too deep TR cavity (Cirruses have barely any volute, as seem to be the case of your WW). The crack on mine was perhaps a tad shorter than yours.
So I took it to a Luthier and he did a good job covering the affected area with ebony and maple. He routed a channel along the whole crack and then he glued in place a piece of ebony. Then he fabricated a volute by glueing a headstock back plate consisting of a maple piece over an ebony veneer. The result is aesthetically fine and I´m pretty sure the bass will never have problems there.
But as kevteop pointed out, the commercial value is unfortunately damaged. I haven´t sold mine because the bass is more than the money that I´ll probably get from it. Although I may end up doing it anyhow as I need to finance my own creations
