Most people just dip a coffee mug in the pasta just before they drain it to keep some water back. I don't think I've ever heard of anyone freezing pasta water.

Most people just dip a coffee mug in the pasta just before they drain it to keep some water back. I don't think I've ever heard of anyone freezing pasta water. As for "salty water vs. salty sauce", the better way from a culinary perspective is both. Over salting one thing to compensate for another thing often leads to uneven flavor; if everything is salted roughly appropriately it all kinda comes together without any extra effort. I suggest trying it, hell maybe even do an A/B test. It's subtle, but salt penetrating the pasta during cooking makes it taste that much better.