(SAMPLE POST, STILL IN DRAFT MODE, LMK IF YOU'D LIKE ME TO WRITE THIS OUT)
In addition to breaking down another barrier, e.g.:
* Forced to find the right grip with 1 hand (exercise in itself)
* Coherent movements (follow the flow vs muscling it), clean contact (to not get off path)
* Can directly compare the swings b/w left and right
* Get into a flow e.g. using figure 8
* Should help improvisation, e.g. on the run
And then?
1 arm with 1 racquet often doesn't look great, tends to cause a tight arm.
So initially more of an exercise to perform perfect strokes with 1 hand.
For classic (vintage?) "1 racquet tennis", and training the weaker wing, go back to using the other hand to support and give temporary relief to the racquet hand.
Personally would love if 2 racquet play was officially allowed (or at least not frowned upon) - e.g. to add variation, challenge, strategic option, etc.
Let's move things forward :)