Consistently high!! Moisture meters will read between 1/2 - 3/4" deep into the substrate. The fairing on the keel is generally less than 1/8". Moisture meters show metals as high moisture on the gauge!! There is no sense in using a moisture meter over the lead or iron portions of a keel unless you have an unusually thick fairing over it.. You can use it over the keel stub but again moisture meters interpret metals as moisture and bottom paints can send the squirly..PS. I have a moisture meter and I checked keel all around it seem that moisture measurements are consistent all around the keel. So I don't think I have pool of water sitting behind that crack...
That crack goes with the territory on an iron keel..