In reply to Mowglee:
Mowglee, Jamie - thanks a LOT for sorting this.
I made an effort getting a whole bunch replaced a few years ago, and had always intended to get around to doing something like this, but never did. The fact you've replaced not only the threads, but removed the chains as well, makes what you've done all the more impressive (I can't imagine that the latter were easy to undo).
There's still a variety of new-ish stuff at the top of various routes that actually top-out, including Great Central Route (E2 5c), Ceramic Extension (E5 6a), One Night (E1 5b) and (if I recall correctly) Sergeyenna (E1 5b) and Two Sunspots (E2 5c); however, the thing we should all be conscious of now - alongside the condition of the static rope - is what that rope is around. If it's ash, which it's likely to be down Chee Dale, then this is a growing concern in light of ash dieback.
This is potentially worth a separate thread in/of itself, but we're looking to implement a reporting system through the logbooks, where you'll be able to submit information such as this, which can then be shared with the BMC and the relevant access reps. It'll also act as an alert in much the same way as the feedback does and is something we should all be keeping an eye out for.
In terms of the longer term solutions there are several options. The easiest is to find a suitable alternative, if available. Chee Dale is predominantly ash, but this isn't to say it's all ash, so there may be something else around. The other option, which is potentially going to be more contentious, is to place a double bolt belay. The likely candidate for this treatment is the ash tree belay/abseil station at the top of Mortlock's Arete, because shy of leaving a load of rusting wires in-situ I think this will be the neatest, cleanest and most subtle solution.
Sorry to digress a little from the original post, but it's all on a similar topic/theme, and is something we should all be thinking about before committing our weight to any fixed gear is what that gear is actually fixed to.