Rodinal at 1:25, especially using Agfa's recommended development times, results in contrasty negatives. One can mistake high contrast for accutance. A properly developed negative using dilutions higher than 1:50 (1:75 and 1:100) produce edge effects enhancing sharpness. The effect is visible but not dramatic. One could argue changing film from Tri-X to FP-4 or T-Max 100 is nearly as effective.
Thanks for this. Thanks to everyone else, too. Good information.