Stump the Christian?

[robvalue]

Even if the traces of supposed interaction could be found, it's (currently) impossible to find out what supernatural agent caused it, if any. It would look exactly the same whether it was your God, Jim's God or a magic crab. Or indeed nothing supernatural, and just some natural explanation we don't yet have. All we see are the natural results on our end.

But as it happens, we don't even find these supposed interactions at all. All we get are anecdotes which we are expected to believe with no evidence. And even if they did happen, the person giving the anecdote is employing the argument from ignorance or special pleading to "determine" causation.