I'd agree with this. I at least saw Gestede have some good games. I remember him looking great at Preston away during Woodgate's good run but he was massively impacted by injuries. Not going to argue it was a terrible signing but it was a sign of things to come that we were signing championship strikers when we were trying to stay in the PL.We won 3 games in the 2017/18 season directly because of Gestede goals or assists, he was injured for over half the season.
He contributed, for the money we paid he should have contributed far, far more, but large parts of the lack of impact are down to the fact he was incredibly injury prone.
He was clearly a big waste of money, and we should never have signed him, but Guedioura was a worse transfer.
£3.5m for absolutely no contribution whatsoever is worse to me.