I've been slogging through ON for a while now, and I have a question that may lead to divergent opinions. 
 
As I read through texts, I can usually get the meaning.  But when I go to the grammars, I slam hard into a level of detail which I think of as "pilpul," the Hebrew word used to describe the micro-analysis of Talmudic scholars.  So my question is this:  How much detailed grammar do you all feel you need to know to read (not write) ON comfortably?  Can you read to your satisfaction without knowing all the different conjugation patterns?  All the different declension schemas?  I know that to write correctly in ON requires orders of magnitude more knowledge; I'm just asking about reading.
 
BTW, in your replies, it might help if you identified yourself as an amateur, a professional, a professor, etc.
 
Thx,
   Alec