There was a link to a discussion on what happens during fractioning posted on XT3. The referenced link with commentary by Fr. Z posted here. The original post by Fr. Allan McDonald can be found here.
What they are basically saying is that the larger hosts used during Mass scatter lots of pieces of the Lord’s Body during fractioning and that they can no longer in good conscience use the larger hosts, and have switched to using a smaller host. Fr. McDonald’s trial with the larger host did show the pieces which broke off from it in detail; however, a similar trial was not done using the smaller hosts. It is possible that they scatter a larger number of pieces, which are smaller in size and harder to detect.
Don’t get me wrong, I completely understand Fr. Z and Fr. McDonald’s concern over the unnecessary and avoidable scattering of the Body of our Lord. However, I absolutely LOVE this reply to the discussion:
I have always felt that the Altar is a table of sacrifice. It is enough to imagine the priest of the OT accomplishing the sacrifice of the lamb by dismembering it in the ritual manner and see the pieces of flesh and blood splattered allover the altar of sacrifice as he divides the different portions. I had a view of the butcher’s shop to see how much blood and small pieces of flesh are scattered all over the place as he cuts them to small pieces.That reminded me about what happens when the sacrifice is offered each day at the Altar. I imagine the flesh and blood of the Lord splashed all over the place. Mercifully the Lord has concealed Himself in the form of Bread and Wine, that we may continue to celebrate the Mass. But how much care is needed in the fraction and cleansing of the holy vessels. And as I kiss the alter to depart, to remember that the table is soaked with the Blood of the Lord spilled to save me and mankind. — Fr. Jose Sebastian, posted on XT3 website 9/6/10