Got in the car to nip to the shops earlier and noticed the clutch pedal was really limp for the first 6-7" of travel, almost no resistance. The last inch or so of travel feels as heavy as normal, although the biting point is now almost on the floor.
My first thought was either master cylinder or clutch slave.
Then it occurred to me that the clutch often briefly feels like this when the car is getting a thrashing - but has always in the past gone back to its usual heavy pedal through its entire travel. So that made me wonder about the fluid itself. I'm 99% sure it was bled when the current brakes went on a few months ago, but whether that was the clutch too I'm not sure.
It's a Helix Organic. Went in with a new DMF about two years ago. I've done maybe 15k miles on it.
Also - and I'm sure this is entirely unrelated - I found this loose sticking out of the plastic between the pedals and the steering wheel cowel. It's broken in two, and one half was in that cowel area before I managed to retrieve it. Any ideas?!