[ttd]

This is a great point and not one that I had considered. I suspect I am the same way - scanning back and forth while studying a diagram.

It's possible this tool may be more appropriate for e.g. presentation of info to a mixed audience. Technical people may have questions that can be answered with detail that non-technical people would find distracting, if it were visible on the main diagram. And "presentation" here could be a literal presentation in a conference room, or documenting something on a site that people visit on their own.

You could make the argument in that example that you should create two diagrams, one for each audience. I think that is a valid argument - but I can also imagine maintaining two separate diagrams that present similar information could be irritating.