The problem is that how you worship has a great bearing on what you belive, and vice versa. Most of these new "hymns" contain lyrics that subtely or overtly contradict true Catholic teaching. We sang one last week in my parish that actually referred to the bread as a "symbol"!! And they wonder why so few Catholics believe in the true presence of Christ's body and blood in the Eucharist! Also, the old hymns are often revised to be more pc and less "Catholic". Remember "Holy, Holy, Holy, Lord God Almighty"? Don't look for the line "tho the eye of sinful man Thy glory may not see" anymore...it's been rewritten to remove the word and idea of "sin" because its just so, you know, negative (sarcasm).