That looks much more like a typical honey locust to me. In a recent thread somewhere, maybe here, someone said that girdling the tree a year or two ahead would cause the tree to shed its thorns. I guess it is worth a try.
All the honey locusts around here appear to be naked compared to any of those shown on this thread. The ones around here are all thornless and yard birds.
You're braver than me. I'd be afraid the thing would pull a Wizard of Oz on me and chase me down the road!
I took one of them thorns to the foot when i was a kid. Went right through my shoe and into my heal. You talk about ouchies.