These are my reservations about Flick's high-line system:
1] It's a style that is not new to football, so top coaches have it's antidote. How do you win the biggest trophies when you will have to face these top coaches and teams?
2] Ok, if you must use the system, then be ready to coach your team to play disciplined intense high-pressing football. Also be sure that you can do it when your best players are not there. Because they seem to be issues, mostly when their best players are out.
Now, by the middle of the 1st half against PSG midweek, surprisingly, Barca's pressing had reduced. Gaps were opening, but PSG couldn't punish them well enough with the young players upfront. You can't allow that drop Barca!
3] I have told Barca faithfuls even last season that, it's not just about the high-line, it's the tools used to prosecute it. I have never been confident with the pace and sharpness of Barca's defence. Against Bayern last season, Barca folks were busy celebrating victory, but I was showing them how easy it was to penetrate there defence-line. It's just that Bayern forward players goofed.
4] Bayern had a beautiful defender in the Asian,Min, last season, but for a high-line, he was too slow. Today the Asian is on the bench and Bayern bougbt, Ta, who has a better recovery speed. It's now difficult to break Bayern unlike last season.
Anyways, I wasn't worried on the weakness I saw in Kompany's defence last season, he was a defender, I knew he'll fix it.
Mr Flick maintains his system no matter what, he's that rigid.
Rigidity is if you have a bench like Arsenal’s. Barca clearly doesn't have that, so what's the rigidity about?!
CONCLUDE
I advice, reduce the high-line in some games when your choice players are out injured.
Also even when choice players are fit, consider altering the high-line when you play truly big teams.
The high-line pattern of football is no rocket-science in football, the answer to it is in the hands of big coaches. Flick should respect those coaches, by being adaptable.
I wish him well.