I think in theory Cech is a great signing for us and the kind of transfer activity we should be undertaking. Is he in decline? I certainly don't think you can definitively conclude that based on a bit if a poor 2013/14. Players suffer dips at times but when you compare to what we have right now, what's available and the pedigree if Cech it makes sense. Maybe it will turn out that he's had his day but even if it does it wouldn't name this transfer wrong. We are trying to push into a very limited group of teams challenging for the top honours. That means we have to be constantly looking to improve our squad even by small amounts and to do that you have to take the odd chance.
Look at Chelsea they have bought players at times and it hasn't worked out but it was never obvious that it would transpire that way and even still they continue because quite often with top players who potentially will improve the team it is worth the risk.
I like the fact he is apparently not satisfied with being associated with a top team but wants to play. That sends a message to me that he still has the desire and drive required to be a great asset.