The scariest is not the people who insist upon assisting at the Novus Ordo because they deny there's anything wrong with it. The scariest is those who acknowledge that it is poison but insist that you must go anyway because of your Sunday obligation.

The priest has an obligation to drink the species of wine at Mass. If he found out someone put cyanide into the wine, is he still obliged to drink it? No! If this is true of physical poisons, how much more is it true of spiritual poisons, as the body serves the soul.

The obligation to go to Mass on Sunday is a human law, instituted by the Church, which is why it can be dispensed. The obligation to keep Sunday holy is a divine law, which is why it cannot be dispensed. Human laws of the Church serve the Faith. The Faith does not serve them.

With this in mind, how can a human law which serves the Faith possibly oblige a Catholic to do something that would endanger his faith? It cannot, for a servant is not greater than its master. The contrary would be like saying the Vicar of Christ can oblige denial of Christ.

"No authority, not even the highest in the hierarchy, can force us to abandon or diminish our Catholic Faith, so clearly expressed and professed by the Church’s Magisterium for nineteen centuries." — Archbishop Lefebvre, 1974 Declaration