Haha must be me! I'm pretty sure my fishing ability had gone out of the window since I started changing things up!
I use size 4 krank on various rigs, blowback on coated braid with a stripped back section or Ronnie rigs with stiff boom or a short coated braid for in pva bags. I have also tried a stiff D rig but not caught on that yet.
One thing I had thought is that it could be smaller carp that maybe don't get hooked well with a size 4. I fish a lot of venues that have a good number of single figure carp.
I'm going to start at fisheries like Wyreside, Clearwater and Lakemore hopefully in the next couple of months so I don't think small carp will be an issue at those places.