Definitely this. I think Rubezic will be fine if played correctly and consistently, I'm just a little concerned that Robson doesn't see it. He's moved Rubezic central a few times this season already. The point about him only being 23 is an interesting one. I guess our signings, in defence, are usually expected to be up to speed when we get them (Scales wasn't quite last season, although that might have just been a Goodwin thing). If experience was an issue, and I think you and Panda are right, then it's all the more bewildering that Rubezic hasn't been given a consistent run. It's really frustrating that we get pumped in Europe when seemingly not playing out best setup. Anyway, the new guy doesn't really solve the problem unless he can either play centrally, or we're intending resting Rubezic regularly. In my mind, him being here makes it even more likely that we persist with Rubezic centrally! It could work if Robson allows Rubezic to be ahead of the other two , but I don't think he will. Rubezic's biggest issue is that his peripheral awareness is pish (which is why he also seems best at kicking it the way he's facing) and he doesn't cover left and right very well.
Anyway, it was an interesting window. I've heard numerous people suggest that it was a good window because we got thirteen players in. Certainly there is credit due to the recruitment staff for an impressive quantity. However, by only having one number eight (and Robson wedded to one formation), all the good work risks being completely undone. No matter how good the other signings are, they won't make up for a missing midfield. We tried bypassing it the other night and that didn't work. I'm struggling to think how we get round the issue in a 3-5-2. I guess we play 3-4-1-2 with two sitting. I always think that's better in a back four (4-2-3-1). The question is who the two sitting are. Out of the options, I'd probably try and play Barron into some form there. He's been good in a two before, I'm not convinced that the others ever have. There's no way on earth that we're competing successfully in three competitions with that midfield though unless we move a player from another position or we intend killing Shinnie through exhaustion.