At first, this idea might seem odd because there is a clear benefit to being able to make selections in check-box mode and not be concerned about what items you click on as your selection is dictated by the checkboxes.
But there are some positives, such as less complexity: If both are linked, then check-marking an item to select it would also highlight it, and vice versa (which is how Windows Explorer works with checkboxes enabled). It would mean you could have check-box mode enabled at all times and use the file displays without forgoing the ability to click on items to select them too. You'd have the choice of using Ctrl to select multiple items, or to use the checkboxes, without having to switch the mode on.
Another way it would reduce complexity is that you wouldn't be able to confuse highlighted items for selected items (these are currently independent of each other). Items to be copied for example couldn't ever be mistakenly interpreted as the ones simply highlighted.
All of this simplifies the check-box mode whilst still providing some of its benefits: like how you can "paint" contiguous selections by dragging from one checkbox to another (nice in general, and if you have full row selection enabled which can make it tricky to cursor box-select items).
Of course, the user would be free to keep using check-box mode as it currently works if they wish. But perhaps there's some sense in making the proposed linked option the default behaviour, letting advanced users disable it for the more nuanced (current) functionality? The option could be named "[Link|Couple] item selections and highlights in check-box mode".
It might also be useful if there was a command to make highlighted items selected when in check-box mode. I haven't looked.
Check-box mode is neat. My only issue is finding that I don't use it often because of the disconnect between selections and highlights.
Thanks.
Opus 13.7