Keith, not odd at all, you use an eye diagram as your avatar and make a point about how equipment measures yet do you actually understand this yourself?
Measurements are a tool that you would use to indicate how your design is progressing, BUT listening will tell you more on how to finalize your concept
The eye diagram is a diagnostic tool (along with jitter analysis) to help the debug or design engineer understand where possible jitter/power supply, data transmission issues etc are in a straightforward manner.
So can you interpret exactly what the eye diagram is showing and give the reasons how does this relate to audio for the capture shot above in your own words?
All of the audio measurements taken by the mags are usually measured on an AP525 or similar a Rhode and Schwartz UPA though these only extend up to around 300Khz. IMHO you need to look well above these BW's to really get to grips with how RF and EMI interact with the design and what impact they have with actually listening.
They are some pieces of equipment that does measure not so good , though sound very fine, other ulrea clean and best measuring (lol) can sound forward, and naim like
(A lot of the Chinese so called super dacs (LKS) that ASR is so found of pushing) yet are give the big thumps up. Some of the dacs are good indeed no question.
That eye diagram would need a minimum of 600Mhz bandwidth, though 2Ghz is more a basic standard for these types of measurements so respectable scope would be required to actually perform this measurement.
There is a place for both first principles and empirical evidence in audio, just the right balance needs to sought.
Anyway, can you explain what the diagram represents by way of what is shown?