Any of the other test methods require a significant investment of time.
At a wind tunnel session, you have two hours, however, you only need about two minutes of data per configuration for analysis. A wind tunnel is a very well controlled environment so if you book a session, you are not dependent on weather conditions, as you are with outdoor testing.
Changing configurations is the main time thief when doing a wind tunnel session. Mechanical changes take the longest. Testing helmets, skin suits, shoes, shoe covers, and calf guards are relatively fast changes. Mechanical changes, like riser stacks and extension styles / angles, need to be well practised so that you don’t waste time which is being charged at anything from £300.00 an hour upwards.
Power meters and speed sensors are not a factor when testing in a wind tunnel. Environmental conditions can still be a factor at a wind tunnel e.g. air density. These factors should be included as part of the wind tunnel calibration procedure. At a wind tunnel session you can expect absolute CdA values, or at least what the industry accepts as absolute values.