That's the misconception about Rodinal it's not the temperature of the deveoper itself that causes any problems it's poor temperature control throughout the entire process cycle including the washing.
Originally Posted by piu58
By working at a lower temperature you're reducing the swelling & softening of the emulsion slightly but it's entirely unecessary if you just monitor all stages of the processing and keep temperatures within +/- 1? C of the initial developer temperature.
I used Rodinal as one of my two main film developers for about 20 years and working at the recommended 20? C was never an issue.