I was doing just this last weekend - a drop cut on the shaper. It was small 3/16" grooves for box panels.

I could not get comfortable with it (it did grab on me once as well), so went to the router instead.

They were relatively short though (12" ish), longer pieces would keep the fingers farther away. Having the stops that others have shown here would definitely help, and as mentioned provide a guide so that the piece does not twist when you are entering/exiting the cut.