That's a rather simple & novel concept. Almost makes me wish I had moles and/or gophers . . . but my Daughter's yard is so plagued & several have been prone to gnawing on plastic irrigation lines - I'll pass this along to them. Thanks!
I recently pounded down some hills and gas-bombed a couple of tunnels with those "Giant Killers." That was a week ago. I haven't seen any activity since then, but they'll be back shortly, and I will deploy more gas bombs. Traps don't seem to work that well for me, even though I take great pains to set them up properly. The moles must suspect that "sumpin's up!" and they go around. I've gotten only one using a spring loaded 3-prong spearhead.
That spring-loaded steel noose setup looks like it might be the ticket. I'll be anxiously awaiting reports of its success.