How would you calculate windspeed from groundspeed, track, and heading? As far as the iFly knows, track and heading are the same thing.
To make such a calculation, the user would need to input actual heading so iFly could compare it to groundtrack.
More specifically, since the windspeed vector is equal to the groundspeed vector minus the true airspeed vector, the user also needs to input enough data for the iFly to calculate the true airspeed.
So, it can be done (my 430W does it), but it cannot be done only with data already known by the iFly; it requires data input from the user.