Why not change? It's a good question. Learning about GA is an investment, getting it coded up and tested is an investment, and the obscurity of GA is going to m

Why not change? It's a good question. Learning about GA is an investment, getting it coded up and tested is an investment, and the obscurity of GA is going to make the code almost encrypted to people who aren't fairly mathy. Although quaternions are definitely crazier than GA, the sad fact is they're much more popular. There's some return on all that investment. It might pay off or it might not. I think it's a design decision.