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tokens: different ZDI observations of the same star. We compare the complexity derived from the observations to the magnetic complexity function in CG18 , , in Figure 1 . Here, Ro is the commonly used Rossby number for stellar magnetic dynamo activity representing the ratio Ro = τ c / P rot of rotation period, P rot , and convective turnover time, τ c . This complexity function was derived by matching the evolution of rotation periods of stars in young open clusters using the relationship between magnetic complexity and angular momentum loss derived by CG16 . The function shown in Figure 1 that provides a good match to the data corresponds to a convective turnover time τ c = 100 and value a = 0.005. The former is appropriate for the spectral types of the secondary stars considered here (Morin et al. 2010 ; Wright et al. 2011 ). The value of a is four times smaller than the one used by CG18 , though we note that this quantity only affects the most rapidly rotating stars with the smallest Rossby numbers and was not well constrained in that study that only dealt with stars with masses greater than 0.3 M ⊙ . In our CV orbital evolution model (Section 3 ), we adopt an intermediate value a = 0.01. The shape of the complexity function, n , which dictates the change in angular momentum loss with changing rotation period, remains the same. It should also be kept in mind that, while n av was shown to work reasonably well for parameterizing real magnetograms (Garraffo et al. 2016 ), there is some arbitrarity in its definition and it should strictly be interpreted only as a relative measure of complexity. The spatial resolution of ZDI-reconstructed magnetic fields is also limited by the rotation-induced velocity shift of surface magnetic features and the deconstructed complexity is inevitably going to be a lower limit to the true complexity. 3. Magnetic Disruption of Angular Momentum Loss 3.1. Angular Momentum Loss Here, we simulate the orbital evolution of CVs, including, for the first time, the magnetic complexity modulation and its effect on angular momentum loss. We use the same spin-down model as presented by CG18 . As systems evolve and lose angular momentum, the orbits shrink and periods decrease. Efficient spin–orbit coupling means that the secondary stars spin up, maintaining synchronicity between their rotation and orbital periods. Figure 1 indicates that their magnetic complexity will also increase as they spin up. The data show a somewhat steeper increase in complexity for the stars with the shortest rotation periods, although data are lacking for periods less than 10 hr. We proceed by adopting the CG18 spin-down model and complexity function, taking Figure 1 as offering some empirical support (with the function reproducing well the data on average), but recognizing that it still represents somewhat of an extrapolation to reach the CV period gap. The spin-down model can then be described by the following equations (see CG18 for further details):