I got a call from my younger sister tonight. "Darwin, do you know if a consecration with bread that is probably leavened is valid?"
Circumstances had caused her to go to a different parish than usual (she lives in the Seattle area) for a 5pm mass, and on entering a few minutes before mass she saw on the table in the back of the church a large ciborium full of cubes of what looked like spongy pita bread.
I don't know the answer to this for sure. I'm thinking probably valid but illicit -- after all, the Eastern Rites use leavened bread. But the advice I eventually gave was: If you're really not sure and there's not another mass you can get to, attend but don't receive. You'll know for sure you met your Sunday obligation as best you can, and you won't be participating in the illicit elements any more than necessary.
After getting off the phone, I found myself fuming a bit. Why do that kind of thing? I'm a comparatively laid-back guy liturgically. I'm not one of those types who gets high blood pressure the minute I see a female alter server or an EM (I think we'd be better off without, but resign myself pretty easily), but for goodness sake, what possible good reason is there for messing which the communion species? There is absolutely no difficulty getting hold of real communion wafers in the modern US, and there is no cultural or traditional reason to even think about using anything else in the Roman Rite here. The only reason for it is to be "different" (read: defiant), and really: Why? You're not going to make anyone feel any better (unless its some sort of "we're so open minded" pride which isn't good for you anyway) and it's a good bet that you'll cause someone distress.