Fluted columns aren't really about the pour itself, it's the formwork that gets you. Those flutes need custom liners or shaped foam, and if the forms aren't braced right the concrete blows them out or the flutes come out wavy. Guys try to strip too early too, and then the edges chip off and you're patching every single groove by hand. Seen it happen on a job in Lafayette where the finisher swore up and down it was the mix, but it was really the forms flexing. Pour day is the easy part, the prep is where these things go bad.