Calibration

Hi

First, a few questions about this number:

I guess I should ask: on H5000, I see "Mast AWA". Is that the same as what used to be called "Measured Wind Angle"?

And also; that number includes.., i.e. is "corrected" by whatever is entered as the wand offset - right?

The manual describes a sailing test to correct for mast offset. But what if I measure the offset? Say I observe a 5 deg offset of the wand to port. I would enter -5 deg as my correction, right? It would cause a 10 deg difference between port and starboard, with the starboard angle being greater - right?

Anyway:

I often run into a situation where I believe my wand offset is correct, but I have asymmetric MWA, AWA, and TWA on opposite tacks.

For example; I go head to wind, as determined by my windex, and let it settle for a few seconds. My Mast AWA, and AWA both vary between -1 and +1, so my offset correction is pretty good.

Then i go sailing upwind on port; my Mast AWA is 10, my AWA is 10 and my TWA is 13

I tack, and on starboard, my Mast AWA is 32 my AWA is 32, and my TWA is 44.

So, my min question is: at that point, is it even worth doing the TWA correction as described in the manual (if lifted on both tacks...) ? That correction is assuming a symmetric error.., and i don't have that.

I guess wind shear could cause what i see.., but are there any other causes?

thanks.