##### SUMMARY
<!--- Explain the problem briefly below, add suggestions to wording or structure -->
The [main configuration documentation](https://docs.ansible.com/ansible/latest/reference_appendices/config.html#ansible-pipelining) says that pipelining is enabled in the `ssh_connection` or `connection` section.

The [ssh connection plugin](https://docs.ansible.com/ansible/latest/plugins/connection/ssh.html#parameter-pipelining) configuration says pipelining should  be enabled in the `defaults` section.

#31125 (and the associated commit) seems to imply that the `ssh_connection` section is legacy, but the comments (https://github.com/ansible/ansible/issues/31125#issuecomment-334071699) seem to say otherwise.

The actual sections (as demonstrated in the configuration section below) that works are `ssh_connection` and `connection`.


##### ISSUE TYPE
- Documentation Report

##### COMPONENT NAME
ssh

##### ANSIBLE VERSION

```paste below
ansible 2.9.9
  config file = /c/xxx/ansible/ansible.cfg
  configured module search path = ['/c/Users/bendem/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /c/Users/bendem/.local/share/virtualenvs/ansible-oaopcvR0/lib/python3.8/site-packages/ansible
  executable location = /c/Users/bendem/.local/share/virtualenvs/ansible-oaopcvR0/bin/ansible
  python version = 3.8.3 (default, May 18 2020, 08:39:23) [GCC 9.3.0]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
With `[defaults]\npipelining = true`

```
ALLOW_WORLD_READABLE_TMPFILES(/c/xxx/ansible/ansible.cfg) = False
ANSIBLE_SSH_EXECUTABLE(/c/xxx/ansible/ansible.cfg) = /usr/bin/ssh
ANSIBLE_SSH_RETRIES(/c/xxx/ansible/ansible.cfg) = 1
DEFAULT_HOST_LIST(/c/xxx/ansible/ansible.cfg) = ['/c/xxx/ansible/inventory/inventory.ini']
DEFAULT_ROLES_PATH(/c/xxx/ansible/ansible.cfg) = ['/c/xxx/ansible/vendors/roles', '/c/xxx/ansible/roles']
DEFAULT_VAULT_ID_MATCH(/c/xxx/ansible/ansible.cfg) = true
DIFF_ALWAYS(/c/xxx/ansible/ansible.cfg) = True
INTERPRETER_PYTHON(/c/xxx/ansible/ansible.cfg) = /usr/bin/python3
INVENTORY_UNPARSED_IS_FAILED(/c/xxx/ansible/ansible.cfg) = True
```

With `[ssh_connection]\npipelining = true`

```paste below
ALLOW_WORLD_READABLE_TMPFILES(/c/xxx/ansible/ansible.cfg) = False
ANSIBLE_PIPELINING(/c/xxx/ansible/ansible.cfg) = True
ANSIBLE_SSH_EXECUTABLE(/c/xxx/ansible/ansible.cfg) = /usr/bin/ssh
ANSIBLE_SSH_RETRIES(/c/xxx/ansible/ansible.cfg) = 1
DEFAULT_HOST_LIST(/c/xxx/ansible/ansible.cfg) = ['/c/xxx/ansible/inventory/inventory.ini']
DEFAULT_ROLES_PATH(/c/xxx/ansible/ansible.cfg) = ['/c/xxx/ansible/vendors/roles', '/c/xxx/ansible/roles']
DEFAULT_VAULT_ID_MATCH(/c/xxx/ansible/ansible.cfg) = true
DIFF_ALWAYS(/c/xxx/ansible/ansible.cfg) = True
INTERPRETER_PYTHON(/c/xxx/ansible/ansible.cfg) = /usr/bin/python3
INVENTORY_UNPARSED_IS_FAILED(/c/xxx/ansible/ansible.cfg) = True
```

With `[connection]\npipelining = true`

```paste below
ALLOW_WORLD_READABLE_TMPFILES(/c/xxx/ansible/ansible.cfg) = False
ANSIBLE_PIPELINING(/c/xxx/ansible/ansible.cfg) = True
ANSIBLE_SSH_EXECUTABLE(/c/xxx/ansible/ansible.cfg) = /usr/bin/ssh
ANSIBLE_SSH_RETRIES(/c/xxx/ansible/ansible.cfg) = 1
DEFAULT_HOST_LIST(/c/xxx/ansible/ansible.cfg) = ['/c/xxx/ansible/inventory/inventory.ini']
DEFAULT_ROLES_PATH(/c/xxx/ansible/ansible.cfg) = ['/c/xxx/ansible/vendors/roles', '/c/xxx/ansible/roles']
DEFAULT_VAULT_ID_MATCH(/c/xxx/ansible/ansible.cfg) = true
DIFF_ALWAYS(/c/xxx/ansible/ansible.cfg) = True
INTERPRETER_PYTHON(/c/xxx/ansible/ansible.cfg) = /usr/bin/python3
INVENTORY_UNPARSED_IS_FAILED(/c/xxx/ansible/ansible.cfg) = True
```

##### OS / ENVIRONMENT
Windows 10, msys2 python3, not that it matters.

##### ADDITIONAL INFORMATION
<!--- Describe how this improves the documentation, e.g. before/after situation or screenshots -->

<!--- HINT: You can paste gist.github.com links for larger files -->

raise AnsibleControlPersistBrokenPipeError('Data could not be sent because of ControlPersist broken pipe: %s' % additional)
            elif in_data and checkrc:
                raise AnsibleConnectionFailure('Data could not be sent to remote host "%s". Make sure this host can be reached over ssh: %s'
                                               % (self.host, additional))
        return (p.returncode, b_stdout, b_stderr)
    @_ssh_retry
    def _run(self, cmd, in_data, sudoable=True, checkrc=True):
        """Wrapper around _bare_run that retries the connection
        """
        return self._bare_run(cmd, in_data, sudoable=sudoable, checkrc=checkrc)
    @_ssh_retry
    def _file_transport_command(self, in_path, out_path, sftp_action):
        
        
        host = '[%s]' % self.host
        smart_methods = ['sftp', 'scp', 'piped']
        
        if getattr(self._shell, "_IS_WINDOWS", False):
            smart_methods.remove('piped')
        
        methods = []
        
        ssh_transfer_method = self._play_context.ssh_transfer_method
        if ssh_transfer_method is not None:
            if not (ssh_transfer_method in ('smart', 'sftp', 'scp', 'piped')):
                raise AnsibleOptionsError('transfer_method needs to be one of [smart|sftp|scp|piped]')
            if ssh_transfer_method == 'smart':
                methods = smart_methods
            else:
                methods = [ssh_transfer_method]