Some strange bug in the template module when combining two variables - can someone confirm?

I think I may have uncovered a bug in the template module. Whatever I do, I can’t remove inserted quotes for a dest path which are inserted by Ansible.
The same combination DOES work for other modules.

I have tried using the join filter but this produces the same results!

Below is the relevant debug info:

The version of ansible used:

stan@briar:~/ansible$ ansible --version
ansible 1.7.2