Take the inlet manifold off and have a good look, if the inlets are well caked up, take the injectors out at the same time.get their spray patterns checked, and replace if any are defective.
I've had this problem cured by replacing injector 4, would missfire less the more load that was increased , but would give a feel of an idle speed judder on idle revs.
Steve did yours only play up on idle?
I remember TFSI Mike was having a cylinder 3 misfire which got worse and did it while he was driving, until he replaced the injector.
This carbon build up nuisance has finally been addressed by VW on the mk7, they have put a secondary injector back in the inlet
Mine started as noticeable 'hicuups' on idle/tickover.
Measured on VCDS it would steadily count up on cyl 3.
Got to the point where it would splutter a bit under load.
Then every time under WOT it would be a real bad misfire.
Tried all the usual things. Plugs, coils (switching around didn't move to to different cylinders) had a compression test, new pcv, maf and probably a few bits I've forgot.
Replacing the injector and it was back to full health
Hope you get sorted! Frustrating issue