Quote Hugh Robjohns:
That's probably because you've been doing it for thirty years, John!
Most people do struggle at first to get their head around the concept and then the practical implementation and application.
I actually found it pretty easy from the start.
But I did buy the excellent AES publication on Stereo Microphone Techniques (still in print) and I remember the Wes Dooley and Ron Streicher papers were very good.
John - Sound-Link ProAudio
President - Federation Internationale des Chasseurs de Sons