What do you think is the smallest punch size possible that will remove the minimal amount of surrounding tissue of the FU needed for survival? What is the current smallest punch size used by a hair transplant surgeon in anybody's experience?
Smallest workable size? It depends on the grafts and the patient.
A single-hair graft on a patient with thin hairs? Some docs might go down to 0.6 mm.
A four-hair graft on a guy with thick hairs? 1.0 mm might be justified.
If you cut too close to the graft and you don't nail it perfectly then you're just transecting grafts. Some transplants that used large punch sizes have produced pretty good thick hair in the recipient area. It's the donor area that suffers from big punches.