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tokens: axial fluxes, and encircled by the same twist field present in the two original tubes. In this way, the helicity, in the form of twist, inverse-cascades to ever larger scales. The PIL forms a natural boundary of the flux system: when the twist reaches this boundary, it cannot proceed further, since all of the flux has already reconnected. The end result of the process is a mostly axial and untangled field throughout the interior of the region, and a highly sheared field concentrated near the boundary of the region, i.e., at the PIL. This is precisely what is observed as a filament channel. The smooth internal field corresponds to the laminar coronal loops observed routinely on the quiet Sun and shown in Figure 1 . In this way, the helicity condensation model provides a natural mechanism for the simultaneous formation of highly sheared filament channels and laminar, untangled coronal loops. These two, seemingly unrelated features of the solar atmosphere are actually created by a single process (Antiochos 2013 ). The helicity condensation model was initially simulated by Zhao et al. ( 2015 ), who injected magnetic helicity into a plane-parallel Parker corona (Parker 1972 ). In the plane-parallel representation, the boundaries of the region of imposed twisting flows serve as the boundaries of the flux system, in analogy with the PILs in coronal-field configurations. Those authors found that photospheric motions that inject the same helicity everywhere form filament channels at the flux-system boundaries. Furthermore, randomizing the photospheric motions while keeping the same helicity injection rate did not qualitatively affect the accumulation of twist flux. Zhao et al. ( 2015 ) also tested the effect of injecting helicity of opposite signs on adjacent flux tubes, and found that their fields could not reconnect due to the twist components being co-aligned. In subsequent work (Knizhnik et al. 2015 , hereafter KAD15 ), we rigorously tested the helicity condensation model. We found not only that it qualitatively produced results consistent with the properties of filament channels, but that the inverse cascade of magnetic helicity due to reconnection produces a twist flux at the boundary of the flux system that agrees quantitatively with the predictions of the helicity condensation model. Based on this result, we estimated that with the helicity preference observed on the Sun, filament channels will form in about a day or so, in agreement with observations of their formation (Martin 1998 ; Gaizauskas 2000 ). We showed that helicity condensation agreed both qualitatively and quantitatively with observed properties of filament channels, and that the process produced a much less twisted coronal-loop region away from the flux-system boundaries. Those results were obtained for a 100% helicity preference, however, meaning that all of the helicity injected into the corona was of the same sign. An obvious question to be raised is: what happens if a