I'm not an expert on the 120 year history of Rodinal so Ian Grant would be the guy to ask about tweaks and changes Agfa made over the decades. My understanding, for example, is that the original formula contained no restrainer (I could be wrong) while more recent versions contained bromide. The concentrations of p-Aminophenol and Hydroxide apparently also changed, but again, best to contact Mr. Grant.
Regarding "finer grained Rodinal", don't get everyone started on all that craziness again. Agfa made something called Studional or Rodinal Special. Whatever. Is Rodinal even that "sharp"? Oops... Bracing for impact.