I'm not sure what you mean by this: "play song x by artist y from album w".
I mean to play an episode by the episode number we would need the tvshow title, what season it is and then the number - x - y - w.
But not something VC could do as the phrase would be the same, unless the phrase contained the show title and episode title, as you say this seems like an unnecessary waste of processing power.
We could do the same thing with episode names, allowing for the clarification of what series we want. We don't need to use albums and artist for music (artist is enough) and similarly, for TV we don't need to specify the season, just the name of the show, since for any given show the episode names are sure to be unique. Again, this is something I would never use, but it can be done without too much difficulty. It's just that I think it would be difficult for the user to actually use these commands, so why bother using up resources on storing all those word combinations...
Interesting idea, specifying TV show title to call the episode would alleviate the problem of episodes with the same name. However, creating a payload with show title and episode title seems like an awful long phrase, even using two payload xml's.
Saying just the episode title seems a lot easier.
I am curious though, if you have all this functionality with VoxCommando, what do you use to play episodes? I know there is the navigation commands for XBMC built into VoxCommando, but why use those when you can just say the episode name? I like that I can add new episodes, they show up on the home screen, and I can just say the episode named to play it. Completely hands-free.