No wait, now I can :)

As you can see, the linked article concerns treating intracranial cerebrospinal fluid cysts when treating hydrocephalus (and is effective as far as I know). Now: what does this treatment have to do with the cyst presented in the original blog? The purpose of the shunt in your link is to allow venting of cerebrospinal fluid. Is the cb-fluid flow somehow blocked in the case of the autistic brother in the blog or is the cyst located in a place where shunting does not make any sense?

The cyst mentioned in the original article (and shown in the MRI image at the top) is a posterior fossa CSF cyst that most likely formed as the result of hydrocephalus. Basically, it's the same thing. This is an example of how confusing all of the terminology underlying autism is. In some patients, CSF cysts, hydrocephalus, Dandy-Walker Variant and "autism" may all be very much related or referring to the same thing.

And to your earlier point, that SpringerLink article shows that they've been draining such cysts with shunts since at least as early as 1985, even if they didn't necessarily know what leaving them in place might result in later in life.

What do you find confusing about these different medical conditions? Hydrocephalus is a condition that can arise from various defects in the brain, Dandy-walker is defined otherwise. Do you think that a CSF cyst is required for an individual to develop autism and if so, wouldn't the link be kind of obvious to medicine at this point?