I now there's only one stabilizer between those struts, and only 1 elevator on it, but the way I saw it was that it's representing blowing HALF of it off... Makes it an even footing with other planes that can take partial damage and limp away.
I thought it was a concious choice, rather than an oversight on HTC's part.
EDIT: I've also (recently) seen a P-38 damaged and still manuvering with only half of the stab in place (starboard side if I recall) with elevator on it, port elevator and port stab missing. This was during the scenario frame 1.