In reply to Calum Muskett:
I think that your presentation of the issues is slightly disingenuous. Replacing the pegs on The Strand isn't really like replacing the peg on Barbarossa. I climbed the Strand several times when Drummond's peg runners were still ok, but never clipped them because even then they made no difference to the grade. It is, however, a great example of how routes that see a bit of traffic remain clean and therefore onsightable - unlike most of its surrounding routes nowadays.
Barbarossa pegless onsights frequently (normally?) used a skyhook runner, which does have potential for rock damage in the event of a significant fall. After the E7 start, the rest of the route is no more than E4, so it's a lot more disjointed than the E5/6 version with a peg. And somewhat prone to lichen, though less so than routes further left.
Most people reading this debate will be unaware of the technology involved in the pegs, so will surely be assuming that replacing pegs simply postpones the issue as the rot sets in again on day 1. However, these are stainless steel and designed to eliminate any fracture propogation. They are placed using a rubber mallet, to avoid flecks of steel that cause chemical degradation. In vertical or slanting cracks some resin is placed, so that the peg doesn't dislodge over time. If this technology had been available 20, 30, 40 years ago, the discussion would have been simpler as the decision would genuinely be about the real issues: does the peg improve the route or detract? We need to balance this against the specific environment of this crag. Without exception, all the routes with one very hard crux sequence and no protection above foot level at the start of the sequence quickly become covered in lichen, so that you either need to invest a day or two wire-brushing the route, or respond to the beta when somebody else invests that effort.
Some people might say "well, if nobody is climbing it, let it go back to nature". There are plenty of examples of that around the UK. But most of those routes were poor, which is why they were neglected. However, these are quality climbs and the amount of traffic they received this year (you can read the feedback in UKC logbooks) shows that it was not a lack of quality that was leading to their demise.
But while we are on the subject of easier routes and "progress" what about the dozens of pegs that make an important component of the belay? Back to the Strand again, for example. This has had stainless pegs as the belay for a decade now and hardly anybody has even noticed, although I haven't seen many people refusing to use them. But the Red Walls, famed for being serious, have loads of peg anchors, including some of the belays. These are less prone to lichen growth, so these have not had the same attention as Upper Tier. But there are several 3 star classics that are not exactly clip ups(!) but will become extremely serious, and just as loose, when the pegs have rotted (perhaps the protection is already illusory). We have the technology to replace these with a permanent solution. No more peg scars, no more rotting gear. Just a runner.
So by all means, let's have a discussion, but let's be clear about what we are debating. Things have moved on since the "thin end of the wedge" discussions about bolts. We can set rules for where stainless pegs can go (incidentally they are currently only placed in existing cracks or holes, and only where pegs protected the routes as they appeared in the classic guidebook of their era). I think that the least that people who argue for their removal can do would be to commit to helping with the wire brushing every year or two, so that it remains genuinely possible to onsight these routes.
Incidentally, I have not placed a single one of these pegs, indeed I've only even clipped one or two of them. But I think that they offer a technological solution to a perennial issue of sustainability. It would be great if people who know these routes well can decide on a case-by-case basis which ones would benefit from this treatment, rather than getting drowned out by what works on different cliffs with different rock type and different micro-climate. Personally, I think a couple of them would be better removed, but there are a few other routes that would benefit from them - one example being the Wastelands, another perhaps being the Gauntlet (even if just a ground anchor). People who know these routes and their history will know what I mean.