For every test-group and variable-group pair, decode its incidence subset from the shared wire bits, or use its unique forced subset when C_gh=1 and there are no wires. Their union determines S_i within every test i of the test group. The tensor entry is product_i [z_(i,S_i)] Bbar_i(z_i,V), multiplied in the shared ring B_(n+1,n+1). This equals the indicated coefficient in the group product because different tests have disjoint incidence coordinates. Do not multiply coefficient sums of the factors; retain V throughout. Any invalid subset index gives entry zero. An empty test group contributes one.