Independent drugs (A+B = 0.30, the Bliss expectation): p<0.05 for a Bliss difference with one plate's wells as n 42.0%; with one ratio per experiment (n = 5) 5.2%; HSA 'synergy' across experiments 100.0% True synergy (A+B = 0.225, 25% below the Bliss expectation): p<0.05 for a Bliss difference with one plate's wells as n 73.6%; with one ratio per experiment (n = 5) 68.4%; HSA 'synergy' across experiments 100.0%