UCC29002 Load share controller suffers when grounds are different

[Faringdon]

Hi,
The UCC29002 load share controller makes multiple smps's share current when pllel'd.
But if the local ground at each smps is different, then the sharing will be compromised.
Why is there no chip which deals with this "different local grounds case".
When many smps's are pallel'd, there is a hugh chance that local grounds will be different.

Clearly a "digital share bus" is needed, even a PWM to analog converter, so that local gnd differences are cancelled out.?

Attached is a mock up of UCC29002 in LTspice

UCC29002
https://www.ti.com/product/UCC29002?utm_source=google&utm_medium=cpc&utm_campaign=app-null-null-GPN_EN-cpc-pf-google-eu&utm_content=UCC29002&ds_k=UCC29002&DCM=yes&gclid=Cj0KCQiAofieBhDXARIsAHTTldo3PiowaXl-Mu1llS0D-XXzsOV0pcdgHZlHHrO01wq6cEhATG8RVB4aAovBEALw_wcB&gclsrc=aw.ds