Clutch query

Skoda Octavia VRS PD 170 56 plate.

Had the usual clutch pedal sticking halfway up and duly assumed either master cylinder or broken clutch pedal mount. Had pedal checked and master replaced and after 50 miles it was back worse than before so much that I was having to put it in gear and then start the engine as clutch just didn't work at all.

Now for the question!

Took it back and allegedly they have fixed the problem.

As it was explained to me there is a valve/acumalator between the master and slave that limits the flow back to the master when the clutch is released and this had failed. This is a new one to me the only thing that I am aware of between them is the external bleed valve, have I missed something?