[squidgyb]

I must be getting fluent in raaaidalese or something;

What he means is marrying the two ideas - his original changing of the fov, with the 3D window idea - but having his change of fov as a digital, two setting affair controlled by a button, rather than an axis.

When you pressed the button, it would be a little like a zoom out, and as long as the fov is still "connected" to the head tracking position, the impression of depth and viewing "through a window" would remain, though the fov would be much larger so I'm not sure the illusion would still work properly.