Sometimes by going so attacking you can let yourself be open at the back but with 231 goals for PSG I don't think they were bothered.
This is a video test with a few teams to give you an understanding of the teams suited to this tactic
All instructions are in the video if you cant download
It is to my understanding that the tactic was originally a knap tactic but has been tweaked by fishman form my discord so props to both of them