Without reading further. I'd say yes and no. No for client javascript. Compilation is a slow and intensive process. You don't have the time to optimize the mou

Without reading further. I'd say yes and no. No for client javascript. Compilation is a slow and intensive process. You don't have the time to optimize the mountains of code loading on every new page. It makes the page much slower to load. The returns are negative if all the code executed turned out to be a single function to flash a menu, before the user left. Yes for server javascript. It's long running processes, web servers should take time on startup to perform JIT compilation. It's beneficial in the long run.