My mother made something simliar once:
It was a cornish game hen stuffed inside a chicken stuffed inside a turkey. She de-boned everything (they were sliced open underneath, the bones removed, so there was a big cut in the underside). She included stuffing around each item, though very little fit into the birds. I'm not 100% certain, but I think she removed the legs altogether.
Was it good? Of course! Everything my mother cooks is absolutely delicious! However, she never repeated the experiment for several reasons: It was a great deal of work, the presentation wasn't very pretty (no bones = a big blob, not a pretty turkey), and we ended up with an excessive amount of meat and not enough stuffing.
I've seen a frozen TurDuck (or something similar) for sale at Harris Teeter. I considered buying one this year, but my daughter expressed an interest in learning to cook a turkey, and I wanted her to do "the basics" for her first time. The Harris Teeter item was $40 and pretty big -- it looked like a decent value for something that wouldn't have taken much effort at all.