Yup just as if a team was using solely a congested schedule as an excuse -as Klopp is prone to do- for a bad performance. Its various reasons, but if youre a Chelsea player going to a full WHL or Anfield they know what a rush that is. Any performer - a live band will be more creative, show offy in a live gig than in the studio. Its the cheering and abuse that makes it.
I would say players right across the board are slacking off 10-20%. No adrenaline rush, like a training game for some of them. They still get their 150k a week