I've only watched one game he's been involved in and that was the Paraguay-Spain match. Arguably the best game of the tournament and a far superior Spain were a converted PK away from elimination from a far inferior side (at least on paper). I was very impressed with what Tata was able to accomplish tactically.
Essentially, he is a younger, less controversial Bielsa. Not a bad move and according to what I've read, his philosophy closely matches ours. He has the tactical nous to know how to tinker with the team, which is what we will need against Pep. A Barça-Bayern rematch next year will be almost a chess match between Martino and Pep, exactly the coach we need.
My only concern is can he control and manage a star-studded team like this with a lot of egos. Since Messi pretty much made this call, I am a bit concerned with Neymar's development. Perhaps Messi wanted a coach that would show him more favoritism than Neymar? Idk I just hope he can bring out the best in both Neymar and Messi and help develop our young players (Tello, Neymar, Montoya, etc.) and promote the youth again.
I see a 3-3-1-3 in our future lol...
VV
Puyol-Silva-Piqué
Cesc/Xavi-Busi-Iniesta
Messi
Pedro-Sanchez-Neymar