It's hard to see how their combined story of madness and obscurantism tallies with stuff like this from The Blue Book (p45):
When we think about the relation of the objects surrounding us to our personal experiences of them, we are sometimes tempted to say that these personal experiences are the material of which reality consists....
When we think in this way we seem to lose our firm hold on the objects surrounding us. And instead we are left with a lot of separate personal experiences of different individuals. These personal experiences again seem vague and seem to be in constant flux. Our language seems not to have been made to describe them. We are tempted to think that in order to clear up such matters philosophically our ordinary language is too coarse, that we need a more subtle one.
We seem to have made a discovery -- which I could describe by saying that the ground on which we stood and which appeared to be firm and reliable was found to be boggy and unsafe. -- That is, this happens when we philosophize; for as soon as we revert to the standpoint of common sense this general uncertainty disappears.
If you're this strongly against both stupid individualism (perhaps to the point of solipsism) and the idea that (in the face of it) philosophy needs a special language (like mathematics), it seems obvious to me that the very worst way to approach someone like Wittgenstein would be through his (let alone his family's) biography.
