Kovač's worst game yet?

Kovač had a pretty poor coaching performance in my opinion. Specifically in his decision-making regarding the substitutions when chasing a measly, un-threatening one goal lead at home.
Following Svensson's injury against Lille on Tuesday, Bensebaini was back in the squad, and Kovač decided to ditch the usual 3-2-5 (in possession) shape that is utilised with an inverting LB. A decision I didn't mind, yet it seemed as though without this, they literally were just eleven players on a pitch, with no instruction positionally. Nothing was shown going forward, and as Augsburg went direct, Dortmund were bullied out physically, and the effective high press shown in the first-half in Lille, was impossible to have an influence. However, he had another 45 minutes to sort it out, surely he had something planned?
Not really. He looked weak in keeping the same eleven on the pitch after the break. New faces were clearly needed in this game, and he only realised this in the 63rd minute. Kovač brought out the full-back pairing of Couto and Bensebaini, and introduced Ryerson and Beier, shifting to a 3-1-4-2 shape. Not a horrible idea at first in my view, yet it was the Sabitzer and Duranville substitutions that made me doubt. Leaving Brandt and Adeyemi on the pitch was poor, neither looked as though they would grow in influence. Reyna is much more suited to being a creative spark against a low block than Sabitzer is. And yet again, what I have mentioned about Duranville and Gittens being the duo who can break a low-block, yet he took Gittens off for Duranville.
The Waldemar Anton substitution in injury time tipped me over the edge. Can didn't have an impressive display, and my doubts over him showed at points during the game, yet his alternative is coming on up top for six minutes. No thanks Niko Kovač. Oh, and he also forced Beier out wide again for this change. Yet, we still question why Beier hasn't kicked on at Dortmund. To conclude, Kovač depleted me of confidence today, and I now no longer have any resonation with his thought process, and my doubt for the next few years of this club is becoming terrifyingly inflated.