There is an understandable misunderstanding about the racquet support systems:
No distortion means no stress in the racquet.
This untrue!
A material breaks when the stress, being the force per square millimeter, is too high.
I would like to illustrate that avoiding all the distortion of a racquet during stringing raises the tension instead of lowering it.
The picture below comes from an old lecture about stringing and stringing machines:
It compares a racquet with a beam in a wall.
The beam will break under the load of the force F1 if there is no extra support..
* Without support the maximum distortion will be in point A. (3 o'clock in the racquet)
* But, there will not be any stress in the part between A and C it just hangs freely.
* The support in point A introduces a stress between A and C.
* With the support near point C there will be no stress at all between A and C.
What is best for the beam??
The support in A is direct and in C indirect.
ompared with a racquet inside is direct and outside is indirect.
Iow: The outside supports introduce stress in the racquet they do not prevent it.