Wilhelm Johnen's book - true or fake?

[Nick Beale]

Isn't the point that it would be quite difficult to see past the pilot of a 110 if you were behind him? Narrow cockpit, lots of glazing bars on the canopy etc. Something literally dead ahead and level would probably be obscured by the pilot unless the 110 was weaving.

The binoculars aren't a problem, lots of RAF sortie reports talk about the observer using "night glasses."

I don't think the points that were mentioned undermines Johnen's book though. More likely they're quirks of translation or memory, as others have suggested.