A comparison is made between Greaves, E. D., Bracho, C., Gift, S., and Rodrigues, A. N., 2021. A Solution to the Pioneer Anomalous Annual and Diurnal Residuals, Progress in Physics, vol. 17, 2, p. 168. and Hodge, J. C. 2006. Scalar potential model of the Pioneer Anomaly.arXiv: astro-ph/0612567v1. Both papers suggest the Pioneer Anomaly observation is due to the signal being modified by a characteristic of space that is influenced by the Sun and Earth. The papers differ by what that characteristic is and how it influences the signal. The former paper uses "energy density" (a scalar) which is proportional to distance (r^−4) from bodies. All thecharacteristics of the former paper were accounted in the original calculation of the Pioneer Anomaly. The latter paper used a vector proportional to r^−2, a gravitational force exerted on photons that was not accounted. The different treatment of r by the latter provides a more accurate treatment of the periodicities and all 10 anomalous characteristics of the Pioneer Anomaly. The conclusions of the former that the velocity of light is Galilean additive and the use of the "gravitational density" are not supported.