I'm not sure, I don't boot the game in any alternate version.

So I recorded a video and uploaded it to youtube. its still rendering, its only 3 minutes tho so it'll be done soon. I show multiple foggy planets, you can see Titan with clear weather around 2:00

I'm on a Nvidia 550ti and my pc is from 2011. The game has pretty low specs so it runs fine for me. From what I can tell after booting it might have something to do with shaders not loading.

My thought was that it might make more maps visible, I have ZERO issues seeing things on Titan.

So I don't know how useful it would be to speedrunning as a whole and I'm not entirely sure what it is that's causing it, but fog doesn't seem to affect my game at all. I assumed it was because of hardware because I've never played modded trying to test stuff. I'll try to supply some images and/or video for it later in a vanilla game. Regardless I don't entirely know if it is even useful for speedrunning but I wanted to bring it up just in case. It'd be interesting to at least figure out a vanilla way to basically nullify fog.