Unable to disable connection sharing

[Damien Miller]

On Fri, 29 Sep 2017, Dale Worley wrote:

> I'm unable to disable connection sharing using command line options when
> connection sharing is enabled in ~/.ssh/config.  Neither '-S none' nor '-o
> ControlPath=none' prevents ssh from attempting to open the control path.
> 
> I am seeing this problem in obsolete versions of OpenSSH (6.6.1p1 and
> 6.9.1p1).

It's possible that these old versions are interpreting "none" as a path
and not a request to disable it but it's hard to tell without 
"ssh -vvv" output.