Cory Doctorow has plugged this on his blog, which is usually a good signal for me.

That’s about twice a ‘normal dose’ and in the realm of what Terrence McKenna would call a ‘heroic dose’.

Mushrooms vary a lot in real potency but at that level of dosage ego death is almost guaranteed, and it’s likely that the user will spend at least 30 minutes to an hour unable to articulate language.