The initiation of the Suzuki cross-coupling polymerisation with a fluorene-based AB-type monomer was finely tuned within the chain-growth regime by the suitable control of the species generated by the Pd(AcO)₂/t-Bu₃P/K₃PO₄ catalytic system. The prototypical poly(9,9-di-n-octyl-fluorene) was obtained with extremely fast (1 min) polymerisation rates, excellent polydispersities (1.16) and molecular weights dependent on the monomer/catalyst molar ratio, without the need to resort to formal chain-initiators.