I strongly suspect that the primary result of such an algorithm would be very wide error bars on the timeline, and that it would indeed outperform most experts for this reason. You can't get water from a stone, nor narrow estimates out of ignorance and difficult problems, no matter what simple algorithm you use. Though I would be quite intrigued to be proven wrong about this, and I have seen Fermi estimates for quantities like e.g. the mass of the Earth apparently extract narrow and correct estimations out of the sums of multiple widely erroneous steps.