How the hell am I supposed to know if someone's Polish diction was any good? For that matter how do I know that they didn't double half the double consonants in an Italian aria I've never heard before? I think that knowing the standard top 25-35 (about 50 for sopranos) is a lot to expect from a panel. If you're going to start playing stump the band it's not going to do you any good.
Again, if you have a true connection with a certain repertoire, then by all means sing it every chance you get. You might even list it as an extra aria on a list. Who knows, there might suddenly be a demand for someone who can do certain things. Certainly if you can learn rhythmically complex atonal music you should advertise that ability. Not everyone is going to be able to do that well (especially on relatively short notice) or if you have spent a good deal of time learning good Bach performance practice, who knows that could be a big part of a career right there. But for yap auditions? Most of the off the beaten path arias are just not useful in getting hired. There will always be exceptions (if you are a lyric mezzo and you find a kick ass aria from some hardly done Marschner or Schubert opera, that's great.
Let's face it, the five arias in four languages format for most yap auditions already means that at least one of your arias is not going to be a top 20 opera. (Are any English operas even in the top 20? Any French other than Carmen and maybe Faust? Any German besides Flute?) So for that reason I don't think there's much reason to get too far afield for Italian. The fact that they require English means that you are probably going to offer something a little obscure anyway. There's no reason to complicate the list further by going out of your way to offer things they haven't heard before.
Houndentenor
"Unleash your ferocity on an unsuspecting world." -- Bette Midler
