Seems like a really stupid idea to me. Ford put it there for a reason. It's there to catch some of the air and flow it upwards onto the sensor.
If you read below it also says that it tends to make the car run lean at WOT. And IMO I'd always rather be rich than lean.
The mass air meter is calibrated to read a certain amount of air passing by....porting it will frig up the settings and it wont run correctly! Will it run? probably, BUT why risk goin lean, etc for basically no increase in power.
I did it and have had no problems at all. But I spent six hours porting and polishing and should have spent that time doing something else. I felt no gain.