The sliding mitre fence is in front of the bit, cutting direction correct (right to left). I'm not that green!
There is a small depth stop on the mitre fence, so the wood was pulled back to the mitre fence, and away from the cutter down to the stop.
But (hindsight is wonderful) The wood edge to be cut was too far away from the fence and i did not have sufficient force away from the cutter.
the wood edge was very angled, first thin slice only cut about an inch along the wood, but the second slice hit a grain twist and the cutter dug in. Game over.
Very annoying, that cutter was very sharp and working well. Shame about the operator.