Tenons? For a chair or something? I've done it, and probaby will again, with a tapered cutter. (and drill the matching holes with a tapered bit, also in a brace). It's not that hard, assuming your cutter is good and sharp, and you've preshaped the tenon with a plane so the amount of material that has to be removed is small. Is it more work than some power tool? Sure. Is it less skilled to use the power tool? Yes, that too. But this is not really the sort of thing that you would be thinking "geez, there should be a machine to do this" the way a long saw cut or flattening a board with planes gets you thinking.