configure.zcml:

<browser:page
    name="conversation_view"
    for=".mydexteritycontenttype.MyDexterityContentType"
    layer="plone.app.discussion.interfaces.IDiscussionLayer"
    class=".classified.ConversationView"
    permission="zope2.View"
    />

Define an interface IMyDexterityContentType groked schema, I added:

allowDiscussion = schema.Bool(
title=_(u”Allow Users to Comment”), description=_(u”Allow users to commemt on you. Comments
are shown at the end of each page”),
required=True, default=True,

)

and added this class:

from plone.app.discussion.browser.comments import CommentsViewlet class ConversationView(object):

“”” Ability to either allow / disallow comments based on schema
option

“”” def enabled(self):

return getattr(self.context, ‘allowDiscussion’, False)

This Page