High precision electrical resistivity measurements were made on potassium samples, including a dilute alloy at temperatures between 0.9 and 4.2K. These samples were annealed and deformed by twisting at or below 4.2K in stages, in order to generate controlled amounts of dislocations. The resulting enhancement of the electron-electron and electron-phonon terms is analysed in the light of recent theories based on the anisotropy of electron-dislocation scattering. Difficulties in interpretation in connection with recent measurements below 1K by another group are discussed. Some metallurgical aspects are considered.