Nearly fooled me also!
I have borrowed the said set up from a mate of mine and as yet I've only altered the harness slightly in order to fit better. The one thing I did do was to have in place a chest strap as I found the right side strap buckle dug into the front of my shoulder too much.
The chest strap is not permanent (it was a strap from my old pony set up, but works perfectly well), but if your set up hasn't one, I'd consider this option.
Good luck anyway.
Graham