Paul,
If you already know the answers why do you ask? A wave is a graphical representation of a fluctuation of a physical quantity or quality.
So now consider carefully what a detector is, and what happens when waves encounter the detector to allow it to detect.
A detector is a physical 'lens' medium with 'sensor' links to a processor (brain). The sensor detects the new fluctuations in the medium, which propagate to the brain which then interprets them.
No new 'wavelength' in the medium, = no detection!!
Now brains must interpret the fluctuations, which they do against time, giving the derivative RATE which we call 'frequency'. Now some brains are better developed than others. Most think only frequency, and think its somehow 'real'. but we are after all developing our intelligence to find the underlying mechanism for the apparently illogical effects we call 'Relativity'.
Those effects are only illogical when not thinking any deeper than 'frequency'. As soon as the fundamental wavelength (lambda) is considered, then the constant c = f*lambda resolves to CSL by conserving the formula including a delta lambda (Doppler shift IS of wavelength - astronomy does not work otherwise!).
Each lens is a discrete field (DFM), all light movement is propagation. So it's also curved; AE; "A curvature of rays of light can only take place when the velocity of propagation of light varies with position." (GR. PoR Inferences. Ch 22).
Think that through slowly, visualising it, to give your processor a chance to rationalise and assimilate it (you should get a Eureka moment).
John.
I agree, and falsification is essential, But so is seeking out the "hidden likenesses" and commonality. Otherwise we never progress.
Best wishes
Peter