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Granted, radials reduce ground loss by improving the current returned to the circuit but if the distribution of those radial currents is not symetrical (equal and opposing) it would seem they would not cancel, becoming part of the system radiation resistance not unlike a long wire to an RF ground point.
The function of buried radials used with a vertical monopole antenna is to return the r-f currents induced into the earth by radiation from that monopole and which exist within a radius of 1/2-wavelength from the base of that monopole, back to the “ground” terminal of the transmit system.
The r-f resistance in that 1/2-wave radius is a circuit element of that antenna system, and comprises a loss to the radiation efficiency of that antenna system.
A small amount of radiation is produced by the induced earth currents flowing along each buried radial within that radius, but that radiation is both localized, and horizontally polarized. It can be detected using a current probe, or a field intensity meter whose antenna is physically close to that radial, in its very near field.
But there is no useful benefit to far fields produced by a vertical monopole due to that radiation, because in the far field, horizontally polarized groundwave radiation in the AM broadcast band has very high propagation loss (theoretically infinite).
This is true whether or not the buried radials are symmetrically arrayed, and/or converge at the base of the monopole.