Originally Posted by juld0zer

the factory fireshield over a section of the clutch line near the bell housing is inadequate. it is possible to develop similar symptoms with just normal street driving because of the proximity of the clutch line to the cat.

You did mention that you get the same symptoms after cruising on the motorways which seems odd because the airflow would keep things tame.
With the warm ambients and traffic here in Sydney, i resorted to replacing the fluid with RBF600 and wrapping almost all of the clutch line near the cat with exhaust wrap (both the hard line and the flexible section), all the way to the bell housing.

That cured the issue and i feared the traffic no more. This was before i had the CSC replaced due to fluid loss. I think the dealer removed most of the wrap when they replaced the CSC but i havent really noticed the mushy pedal issue since the replacement. Fluid level is unchanged, colour is perfect. I'm happy enough even thouggh the clutch feels a bit too on/off for me. as in the friction point is very narrow, but im not going to disturb anythinf until it really goes south. good luck!