Can I chain API calls through drush?
Drush can read parameters from standard input in JSON format if you supply the argument --in=json. This is what we need for API chaining, because chaining uses nested parameters, and in contrast to a flat list of command line arguments (the default way to pass parameters to drush cvapi, JSON can handle nesting. So to retrieve the email addresses for contact ID 41194 along with that contact's display name, use:

echo '{
  "sequential": 1,
  "return": "display_name",
  "id": 41194,
  "api.Email.get": {"return":"email"}
}' | drush cvapi Contact.getsingle --in=json