The capacity of spatial multi-touch menus such as FastTap is limited by device screen size. We explore the idea of using multiple tabs to increase capacity - multiplexing the tablet's screen space so each location holds multiple items. Earlier work has shown potential of this idea for smartwatches, but no evaluations have considered larger devices. To assess issues with interference-based errors and spatial memory development, we built two FastTap systems with multiple tabs and conducted two studies. We first tested user learning of 16 targets with a training game, and found that participants easily adapted to the multi-tab model, were able to perform memory-based shortcuts, and made few interference-based errors. The second study used realistic drawing tasks and showed that people successfully used the multi-tab FastTap system, with 88% of selections made using shortcuts by the study's end. Our work demonstrates that spatial memory can successfully be multiplexed, and that tabs are a promising way to increase command set sizes for spatial interfaces.