A) it would have been good but it never happened/it's too late to experience it now,
B) if it happened it would be good
- Is A) a grammatical rule or just a language practice?* (He kind of caved in now and said I might be right, which I am, but please prove it to him anyway. Ta!)
- Do you need to say, "it would have been good but it's never going to happen" to be clear, or is it enough to say "that would have been good" to make it 100% understood that it will not happen or that it's too late already?
* I would say it's neither; that's it just the meaning formed by those words put together in that order. But what should one actually call it?