Actually I paint the same part with different airflow if I need to. Highlighting for example, using highly reduced paint, I will use high airlow for better atomization to highlight the portions I need. then when I am done, I will just use low airflow to deliver one single wet coat for a smooth finish and blending if I want to panel line and decal but don't want to use clear coat. Also very helpful when I want to avoid overspray when painting mirror like gloss black for chrome paint. Lower airflow can deliver more narrow wet coats on the narrower side of the part. Why wont I want to change airflow with the same paint viscosity? A lot of people do it, they just do it with the MAC valve, I prefer using the trigger to accomplish the same task. Like I say, I am not asking others to do it. It is just something I picked up and got use to. Works very well for me. p/s: Oh and controlling airflow via the trigger has a very neat use. Many like to mix paint in the cup by back flowing/flushing, or clean the airbrush using back flushing. If you only hold down the trigger slightly, less paint drops flying around, less bubbles and generally less messy overall.