Seems it is a rare being discussed so far.
While I don't own this particular bag, I have something similar. The Sac Marine in Gulliver. Drawstring closure with single strap that can be thrown over your shoulder or across your chest, bandolier style. It has a casual look to it, but things tend to get "lost" in it. Also access to the bag is a pain, but I really do love it.
I love these bags aswell: there's a very nice toile/leather one in H S/S catalogue, but I also think like HG that it's not very practical...pitty