yup that's why you need to put grease on the clutch slave rod coz it expands when hot, too tight tolerance.
The greasing and cleaning has nothing to do with the tight manufacture tolerances. Tight tolerance is tight tolerance, no matter if you grease it or not. For 1199 Owners with tight tolerance issues - the clutch master gets stiff. Meaning the metal expands with the heat which greasing will not cure.
Only cure for tight tolerance problems or stiff clutch action is: Remove your piston slave, scotch brite it and apply a metal polish compound to polish the cylinder walls. Once Polished, apply heat resistant grease onto the cylinder slave, dab a bit on the rod end and add a thin fillm of grease on the long rod. Then, re install.
A must to replace stock original clutch fluid to
Motul's DOT 5.1 RBF600 brake fluid which has a higher boiling point.
With that all done, problem will be solved 100%. Iv'e done these myself on my previous Ducati's in the past.
Had "similar" problem with my Panigale "S" when I first got it. It had a "Creaking" sound but
never felt stiff. Creaking sound was dryness...and lots of dirt. Infact I showed my bike to Ducati Manila's CEO - Toti Alberto. He felt my clutch and heard the creaking sound...he said to bring it in.
I decided to work on it myself. So I simply removed my clutch slave and cleaned all the filth and grime coming from the front engine sprocket. Regreased all parts as mentioned above, replaced my clutch fluid, now have more than 9,000kms and never had the problem since. I do this every 4,000kms though due to the location of the slave which is in front of the sprocket..thus, Slave cylinder captures dirt so easily.
I just replace my clutch and Brake fluid from time to time as I do lots of tracktime. Frequent trackdays degrades your brake, clutch fluid and engine oil too. So I replace them often. Never had issues since...