That is Feeney teaching. The Dimonds teach the contrary and have to claim that Trent did not teach what it taught to get around it. Both get around the truth in different ways. Feeney was wrong. The Dimonds are wrong.
Well yes, that is what Fr. Feeney taught. He taught that because that is the actual canon from Trent - what would you expect him to teach, that the sacrament is optional? Of course not.
You asked the question, I gave you Trent's answer, you say Trent is wrong. Same o same o.