I'll remove it now. It was useful to have (for me) for GPG version 1 when I connected to machines via SSH and didn't want a GPG agent pop up UI, and didn't have an easy way to change the GPG agent settings.

Contemporary versions of GnuPG (>= 2.1 IIRC) always use gpg-agent, and this option does nothing except producing a warning:

  gpg: WARNING: "--no-use-agent" is an obsolete option - it has no effect