In one sense I think “gradualism” is exactly what the Church has always taught. Catholics don’t believe in “once saved, always saved” as if holiness or virtue could be turned on or off. Every day is a process of conversion, of growing in virtue and holiness, and sometimes failing. That’s why we have Reconciliation. But hopefully, as someone looks back over their life, they can see that they are more virtuous today than they were a year ago or five years ago or ten years ago.
How that applies to concrete situations is more difficult. The article talks about gradualism in terms of second marriages, but how exactly does that apply? Would it mean, for example, that someone who has applied for a declaration of nullity – and thus is working on resolving an irregular marriage situation – should be allowed to receive communion? The problem is that seems to assume that the previous marriage will definitely be declared null. What if it isn’t? The Tribunal says the first marriage was valid but the couple in the second marriage wants to stay together. How would they gradually improve the situation?
I can see it at an abstract level but I don’t know how it would be implemented in concrete situations.