When two NOTES overlap it's a problem, and Logic keeps the overlapping notes
until you tell it to "remove overlapping notes"
When two REGIONS overlap, that's not a problem, because you would
overlap two regions intentionally, just before you merge them.
Logic automatically erases the overlapping portions of REGIONS.
This is backwards. It was something uniquely crappy about Ableton Live.
But now Logic does it too.
In order to MERGE TWO REGIONS TOGETHER, you almost always
put one of them on top of the other, so neither region should be erased from existence
simply because one is on top of the other.
Overlapping NOTES, on the other hand, are ALWAYS a problem and their
overlapping portions can be erased.
[Edited by Moderator]