[Forward to 1:40 for the magical moment.]
We do understand the tides, actually. Now, if he used an example of something that we don't currently understand, this would be less susceptible to comedic mockery than, "Tides come in, tides go out, you can't explain that." Yes we do. We've known how to explain that for the last couple hundred years. Give a better example. If he said, "There's dark matter and dark energy forcing the expansion of the universe so fast that it's accelerating. You can't explain that." Right! We can't explain it. I don't think Bill knows enough about physics to tell us what we don't understand yet.
But here's the paradox: If he wants to use that line of reasoning for his explanation of God, all we have to do is come back and ask, "If you don't understand something and the community of physicists don't currently understand something, does that means God did it?" Is that how you want to play this game? Because if it is, there's a list of things in the past that the physicists at the time didn't understand. And a talk show Bill might have conducted 200 years ago would have said, "The planets do retrograde? You can't explain that. Must be God." And at the time we'd say, "You know, you're right." And then ten years later we'd understand it. So then what do you do?
Winds and fire and lightning were explained by Aeolus, Vulcan and Zeus. The moon and earthquakes were explained by ravens and turtles. Over the centuries, science has proved physics and evolution as the catalyst and answer for mysteries, and not ethereal deities that judge us from on high. Christianity is merely one of the newest religions to form and try to use their god as the explanation for the currently unexplainable. Until we find the answer. And then it's on to something else to assign "God" to.
If that's how you want to invoke your evidence for God, then the notion of God is an ever-receding pocket of scientific ignorance. It's getting smaller and smaller as time moves on. So be ready for that to happen if that's how you want to come at the problem. It's simply the God-Of-The-Gaps argument that's been around forever.
And for the record, I don't even mind or care if someone wants to say, "You don't understand that? God did it." That doesn't bother me. What does bother me is when a person is so content in that answer that they no longer have curiosity to learn how it happened. The day you stop looking and trying to learn because you're content "God did it," I don't need you anymore.
You're useless on the frontier of understanding the nature of the world.