Unfortunately I have problems with both of those. The first is that I haven't got TOG yet (BLASPHEMY!). Obviously that's an easy fix that I'll probably get on right soon anyway.
The second is a greater philosophical question. There's at least the possibility of unreformed pagan realms with zero writing tradition stubbornly clinging to their old ways, which would reduce their willingness to try out those filthy foreign ideas. For example, it's very possible for the Slavs to kill Cyril and Methodius in this game, leaving them without an alphabet. Would their subsequent technology development match the Muslim world in that case? Of course EU3 undermines this argument by making the highly literate Chinese tech up even slower, but that's tied more to the Not Invented Here syndrome, which persisting pagans would also have, so round we go again.
Simplicity (or my sheer laziness) argues for keeping things as is, with 50-80% of max learning rate getting you Muslim group, 80-85% Ottoman, 85-90 Eastern, and 90-100% Western. I can rationalize the increased minimum by claiming that the NIH attitude just wouldn't function as well in the chaotic cultural and religious soup that is Europe and that writing is not as critical to most technology of this era as it has since become. It's probably unduly kind to an unreformed pagan Iceland that would be quite isolationist as well as isolated, but outliers must sometimes lie outside.
TL;DR: Pode argues himself round to agreeing with the boss that Muslim should be the minimum possible tech group