Class.mark_as_read! :all, for: user doesn't mark all as unread in a transaction

[kenips]

When inside a transaction, say:

Book.transaction do
  Book.mark_as_read! :all, for: user
  Book.unread_by(user)
end

would still return unread books from before the transaction. I understand that this could be by design, but perhaps there could be instance variables set above the persistence level to provide support for this scenario?