By: Mark Glennon*   “Please, don’t go to the top of the curve!” That was the warning from a Wharton School professor of finance, Robert Inman, in a recent presentation he made at the Federal Reserve Bank of Chicago, speaking in general about tax rates for states and cities. What did he mean? Are Chicago and Illinois at the top of the curve? Those questions may seem obscure, but they’re key to our future. Voters don’t just need to asks whether more revenue should be raised, they need to ask whether that’s even achievable. And hang in there on this.