i'm using this tactic with Derby County. Attacking Left Mirror looks great but Counter left Mirror didn't do well for my team. so far, i won 6, draw 2, lose 1.
I have used one of tbhs' tactics in FM13 with Everton and it was very succesfull. It used the same format for the 4 tactics as this one but obviously a different overall tactic. The way I got the best out of that is by constantly reviewing what is going on in the game in terms of match stats and possession and then changing my tactic centred on this.
Starting a game I would always use either attacking or cautious depending on the quality of who I am playing. I would switch from attacking to cautious during the game if I was dominating possession but the opposition were creating too many chances, and to counter if I wasnt dominating possession.
I often switched between tactics 2-3 times in a game and it was really succesfull with my Everton side in their first season (won the league).
I am going to try this tactic in the same way but with City and keep you posted.