I'm not 100% sure this is the problem you had, but it may be...
There was a safety announcement a few years ago re. the Zero4 bar. It should still be somewhere on the PL website I'd guess.
Anyway the issue was that the bar was set up so that when you let go of the bar, the remaining line would run through the middle of the bar (or some constricting ring anyway). The solution was simple enough- re-attach your leash so that it doesn't pass through any hindrances.
The only side effect I've noticed of re-routing the leash is that it dangles below my bar while riding. Fortunately no-one has made fun of my floppy leash yet.