I'm talking about the number of tax rate cuts in real life, reality, the real world. About the only one that I know of that might have proved the Laffer Curve in practice is the JFK/LBJ tax cuts in the 1960s, but those too expanded the base/cut 'loopholes'. That's the 1 time in 100, although the real numbers are likely closer to 1 in 1,000. Doesn't matter for purposes of the example.
So the point is real life examples of tax rate cuts INCREASING revenue are RARE, almost unheard of, and a person adopting the simple position - tax rate cuts will lower revenue (and vice versa) - will be correct nearly every time, and probably EVERY time the issue comes up over an entire lifetime. The person adopting that simple rule is not a 'moron' but reasonable, prudent, rational, responsible.
Conversely, any legislator who actually believes that tax rate cuts will INCREASE revenue is in fact a moron, at least as we sit here in the U.S. in 2017. We're nowhere near the likely top of the Laffer curve of roughly 70%, and states and local governments clearly are not, and so the rule that tax rate cuts will decrease revenue (and vice versa) is in fact the ONLY rational position to take on the front end of any decision to change tax rates.