Point one is not what my experience says. For more than one reason. I look at the numbers below about .200 lift, but unless something is way wrong o don’t care about that.
If you can test low lift at say...100 inches of water you’d see why the low lift numbers don’t mean much at 28 inches. Plus, the piston is in the way. Plus, you have to deal with cross flow at overlap. To fix that you have to reduce overlap and that’s a power killer.