Haha, ok fair enough. In the world of system-level integration of power electronics, SPICE is often considered the bottom. There is already a long way from an ideal on/off switch to a SPICE model of a MOSFET with a gate driver featuring 15 000 variables. Especially for a model that wants to include everything like the controls, the converter, the mechanical load, the thermal and magnetics. But I know that IC design go much lower down. I believe I have seen articles from Xyce pushed to many millions of variables and more. I forget the details, but I think I remember seeing an article somewhere for a benchmark of KLU of an integrated circuit with over a billion variables. We are definitely not at such a low level with our tool.