Thats a good point about maneuvering flight! I'll keep that in mind.
Ideally I would want to measure true airspeed.
I though a bit about using a gps data logger and flying in a circle to figure out wind speed and direction. But it would be a bit of a nuisance.
Wind speed and direction changing with height.
The accuracy of results might be bad. So i'm trying to avoid the gps data logger method at the moment.
The hand held wind anemometer idea sound a bit crude, but it would be interesting to see the data, the error from not having it perfectly aligned with the relative airflow may be negligible anyway.