I went to Darin Morgan's cylinder head seminar last year and one of the tools he uses on the flow bench is a small wing that he moves around in the port on the flow bench. This helps him decide where he needs a wing, or whatever they call it. I have looked at many of his heads and they seem to have some form of this.
There is the other extreme though, years ago my cousin told me to knock the valve guides out on my CB750 and to just smooth the entire port out and to pop the guides back in and do my valve job. My valve job guy said I had ruined the heads, but we went out in a 200 mile race and won the 750 class and took 3rd overall against the 1000's. Sometimes overall flow improvement means more than just smooth flow.