The MuFi approach can easily fail if the energy range from the LoFi scan is not adequately covered by the HiFi data (cf. SI, Figs. and; the same behavior shows for the previously discussed methanol-2-methylfuran dimer, cf. Fig. ). This is because of the linear relationship between LoFi and HiFi data within the MuFi treatment, cf. 4. If the model has learned from regions where both LoFi and HiFi data are available that HiFi data in local minima show lower energies than the reference opposed to higher energies on LoFi level because the conformational order changes at HiFi level, it can obtain a negative ϕ and model the mean µ to largely deviate from the LoFi data, e.g. more resemble a curve mirrored at the angle-axis (cf. Fig. ). Adding one HiFi sample, e.g. the global maximum, allows reliable training of the MuFi model as can bee seen in Fig. . Similar findings pertain to hindered rotations within alcohol dimers and can be solved by the MuFi treatment analogously (cf. Fig. ). We therefore recommend a standardized exploration strategy for MuFi 1DHR PES modeling of not only calculating HiFi data for the global (LoFi) energy minimum and local minima in increasing order, but also adding one high-energy sample, preferably a stationary point like the global maximum. ϕ is close to one. Line and color code is the same as in Fig. ; the standard deviation is visualised as a shadow.