Playbook that demonstrates ssh pipelining not working as expected

playbook.yaml

- name: Make a host list
  hosts: localhost
  gather_facts: no
  connection: local
 
  tasks:
  - name: add host
    add_host: hostname=1.2.3.4 groupname=foo
 
- name: Do the do
  hosts: foo
  connection: ssh
  gather_facts: no
  sudo: yes
  remote_user: dpk
  tasks:
 
  - name: thing one
    copy: src=/etc/passwd dest=/tmp/passwd
 
  - name: thing two
    copy: src=/etc/hosts dest=/tmp/hosts