Consolidating MIDI Notes
The Consolidate command lets you combine two or more consecutive MIDI notes of the same pitch into a single MIDI note.
To consolidate MIDI notes:
1. Select the MIDI notes you want to consolidate.
2. Do one of the following:

Choose
Edit > Consolidate.

Right-click the selected notes and choose
Consolidate.

Press Option+Shift+3 (Mac) or Alt+Shift+3 (Windows) to consolidate adjacent selected MIDI notes of the same pitch.