I agree completely. The key to making effective use of the National Archives is to have sustained access to the collection. Unfortunately, that is impossible unless (1) you live in the Washington area and (2) have a job with plenty of free time or flexible working hours. As you noted, it takes a long time just to understand how the National Archives is organized (or not organized, as the case may be). I found a lot of interesting information during my visits but I can only dream of what I might have discovered had I been blessed with more time and money.