Imagine a box, with a grand staff in the main project window. This staff previews one measure (the measure where the project cursor is). It shows you a simple reduction of the entire score. I want to click on B Natural, use the UP ARROW and have every part change to a C Natural.
The Piano Roll doesn’t sufficiently allow for easy mass editing, because you can have dozens of various notes across each octave. So using the mouse to highlight all of these to make a mass change… well it’s not possible as-is.
Cubase needs more midi mass-editing features.