From: The Practical Woodworker, edited by Bernard Jones
"USE OF FILLISTER PLANE: A plane specially designed for cutting rebates is the fillister... ; it differs from the rebate plane in having a side fence, and in more elaborate forms it is adjustable for depth of cut and has a slitting cutter in advance of the main cutter, so that even across grain it can be used without making a sawcut or marking lines for planting to. But is is used mainly for cutting rebates with the grain, which are often required in joinery, in window sashes, for instance, and in other framework.
There are three types of fillister - the sash fillister... which looks very much like a plough, and is designed for planing a rebate on the opposite side of the wood to that which the fence slides against. There is the moving fillister..., intended for planing rebates on the same side as the fence; and there is the standing fillister, which is not adjustable."
Interesting that the moving fillister is described as intended for cutting with the grain, although it is also effective across the grain.
There is only so much we can infer from the look, feel and apparent use of a given tool. It always helps to 'talk' to someone who grew up with the particular craft instead of using our imagination. Which is why I like the 'old' books.
Till next, Gary