Why use 1d20 vs 2d10? : rDnD

2d 10QCAD is a free, open source application for computer aided drafting (CAD) in two dimensions (2D). With QCAD you can create technical drawings such as plans for buildings, interiors,Also it's faster and easier to balance. Not many people have good intuition around normalgaussian distributions (and 2d10 is a triangle anyway)