Goering's loss of influence was indeed gradual and mainly through 'over-promising and under-delivering'.
The Battle of Britain didn't enhance his prestige and neither did the bombing of Germany. As Kai rightly points out, Goering's main 'fall from grace' was due to the Stalingrad debacle, after which in 1943 Goering retreated to Karinhall, his hunting, his toy trains, etc.
I cite this work with the greatest reluctance, but much interesting information about Goering's career is contained in David Irving's
' Goring ' ( 1989 ) - but it's up to you how you interpret it....
