The strategy is reconstructed for every playbook that is included or
specified on the command line, therefore we can't store the global
Router there without losing all our SSH connections across playbooks.
Ansible's PluginLoader makes up bullshit when it imports a module
(mostly because it has to make up something), therefore we ended up with
duplicate copies of ansible_mitogen loaded: one under
ansible.plugins.*.mitogen, and one under the canonical namespace.
Which broke isinstance().
David Wilson