Blondel, and later Pham and Shirts, derived schemes to select minimum-variance pathways between end-state Hamiltonians. Their derivations assumed infinitely close spacing of intermediate states along the pathway and ignored statistical inefficiencies, which reduced the optimised schedules' efficiencies. Reinhardt and Grubmüller also ignored correlation times but accounted for the finite spacing of intermediate states. There have been attempts to reduce correlation times by smoothing energy barriers, and by constraining the selected path to avoid problematic regions of parameter space. A particularly simple approach is to optimise only the number and spacing of states along a pre-determined path. We limit ourselves to this approach here. Most approaches to this problem involve short initial simulations, although König et al. developed a simple metric to estimate the required number of intermediate states based on the energy difference between minimised end-state structures. Several methods have been proposed that space intermediate states by equal thermodynamic distances. This has been shown to minimise total variance of the free energy estimate for any unbiased estimator, assuming infinitely close spacing of states. Methods which do, and do not, account for the autocorrelation of samples have been suggested. Methods based on heuristics have also been proposed. Recently, Zhang et al. built models to predict non-local phase-space overlap, which were used to select λ schedules with equal phase space overlap between adjacent windows. However, the use of any protocol for intermediate state selection is still rare in alchemical free energy calculations, and extensive investigation of optimal selection protocols and potential benefits is lacking.