The main reason that I think Jeremy is completely innocent of these killings is that he simply isn't someone who appears capable of doing them or of killing his entire family by any method, whereas Sheila, given her history of serious mental illness, could have been. A secondary reason is that I simply don't buy that Nevill's body was mistaken for a woman's body by the police, and then (by a series of coincidences) various radio messages corresponded to exactly what would be expected if both Nevill and Sheila were initially discovered in the kitchen, etc.
