I think that is very much in dispute last season. He certainly has to bear a lot of responsibility on the set piece problem.
I think it is very harsh to lay the large portion blame on Kasper.
For half the season, the problem was the shocking zonal marking system employed.
Switching to man marking helped but it still doesn't solve our root problem with set pieces in that we are a physically small and weak team.
We also employ a bizarre system of marking the opposition's most dominant players with players like Tielemans, Nacho or Thomas when it should be our best aerial players marking the oppositions'.
The fact that we barley ever look a threat from a set piece ourselves confirms the fact that we are poor in the air.
Kasper does have a reluctance to stay on his line, that is obvious, but that is not the main reason with our piss poor set piece record.
Even if he did cost a couple of goals at them last season, I'm fairly certain over the whole season, he still earned a lot more points for us than he cost us.
And that is all before you even consider the leadership and experience he brings to the whole squad which no one else can get anywhere near.
Massive gloves to fill here.