Just had a eureka moment on that,just like in the shower when you get your best ideas or answers to tricky problems. Or is that just me.
Anyhow, if the chain is moving forward through the chain housing it could be causing a forward draft of air thus blowing any oil droplets forward and away from the chain
Anyway, I'm converting mine back to rear sprocket feed.
That's if I haven't sold it first. ( shameful plug).