Select Cable Destination ⇧→
Selects the object that is the destination of an attached cable. Easy way to navigate the MIDI Environment.
I like to think of working in the MIDI Environment as writing assembler (machine) code. Right down there at the bare instructions. Working in the Tracks view is writing Objective-C. Oddly different from C++ or C, but nicely powerful.
Advanced selection commands in the Logic Pro Environment – Apple Support
This function allows you to follow the cabling from one (serially cabled) object to the next. If several objects are connected in parallel, or several cable connections are selected, the path of the upper cable is followed.