I might have figured out the reason why weapons speed up with Cecil's patch. I think their patch might have the weapon slow down bug fixed and that gets added to my fix. You see, the weapon slow down bug happens due to floating point imprecision; The way certain weapons' fire rate and the game's tick rate is calculated, causes those weapons to slow down after about an hour. The game's engine has an epsilon value, that gets added when those weapons fire, to counteract floating point imprecision. But the imprecisions eventually add up anyway, causing the weapon to slow down.
This can be fixed by raising the epsilon value, which I sort of did, by subtracting slightly from these weapons' fire rate. Which makes them ever so slightly faster, but also fixes the bug. Cecil's mod might have also raised the epsilon value, to counteract the bug. The two changes to add up and the gun speeds up.
