@Dumpy , I'll be honest, the only book I read was Jacques Plante's book. And the only video I watched was Andy Moog's.... through the years I did observe the styles of Moog, Hextall, Kirk Mclean to pick up on certain moves in situations.
I am NOT the modern butterfly AT all... if you watch old youtube videos of Stephane Fiset, that is very close to my style.
Sorry I'm not much help as I am mostly self taught.
Oh, I also read Vic Lemire's "Goaltenders Are Not Targets"