I'm not sure, but I think it just puts it in the bin that is highlighted. You can move them manually, if necessary.
I don't think it's consistent. For instance, I'll make the subclip, then go right back to grabbing another subclip out of the main clip - but all of a sudden, I find a whole bunch or in the main project bin. I feel like somehow, the main project bin gets highlighted somehow in that workflow without me actually clicking on it... I hope Adobe is reading this and allows us to set a subclip bin!
And THANKS for the reply, Bob!!
You're correct, CoachNick. There is at least one case where new subclips are placed somewhere other than alongside the master clip. In my experience, this happens when a) two or more Project panels are open, and b) the master clip is in a lower tier in the tree than another Project panel. If these specifics do not match your case, please provide more information.
So a workaround is to close all other Project panels when subclipping. To minimize the pain of this, you can make use of custom workspaces to conveniently flip between a layout with only one bin and your preferred or most recent layout.
This issue was found too late to be fixed for the current version, but there's a report open for future attention.
As for a new feature to allow the subclip destination to be specified, feel free to enter your request here: https://www.adobe.com/go/wish