From this closed NL bug.@Crane - can you remember exactly how you managed to set this up in your screenshots? I'm having difficulty replicating exactly what you have there.
However, I have noticed that this happens, and I wonder if it's one and the same bug:
Left: Fencer seems to be able to continue past the steel | Right: Fencer has found steel and stopped working, but walks forwards rather than turning, and the "chink" sound isn't cuedI'll try to find a fix for this.