The fluid gets dirty fast from the amount of travel and frequency that the clutch pedal is pressed. It is many times more than the brake master.

Change it ever 5k miles, it should take you 3-5 minutes. you don't even need to bleed it or flush it. Empty it with a turkey baster, clean it out spotless with paper towls, and refill it.

Mine leaked bad when I first noticed it, it has since stopped. Just like a few other hundred s2ks have stopped.

I also find that ATE super blue will stay cleaner longer. If you switch to super blue, you will then need to do a flush.