I see from one of your comments that you are tagging for the renderer :-

'East Moor's delineation had disappeared from the map. Seems it was changed to "Natural" from "Heath", so wasn't rendering as a moorland. Changed back.'

That is horrific. Removing ground truth and replacing with an invention. This is not what OSM is about. We want a reliable honest map: not a series of inventions to make the rendering pretty.

If you don't like the rendering, fix that, not the facts on the ground.

You have also changed Twelve Men's Moor back to the ridiculous heath. I would have suspected vandalism if you had not replied.

I have just come across Inn Down!
If you had looked at the history, you would have seen that I had corrected the original "heath" rubbish, yet you come along and reinstate it!
osm.org/way/391660464

About the nearby areas marked as "heath". Many of those mistakes had been corrected. They too were from armchair mappers with no local knowledge or survey. If we have to give a natural tag on such a coarse scale, the best is "unimproved grassland". I can't find that tag for now, but I will change at least some of the mistakes to at least grassland when I have time.

Another quibble. You left the source tag as "local_knowledge; mapbox". But that was for the original mapping, not for your changes(s). So we now have wrong data apparently from "local_knowledge" which you don't seem to have.

Christ Church, Oxford includes the Meadow.

Craddock Moor?? The whole area? And yet more "heath" ?

Craddock Moor is just a section in the SW.

Again, there are some portions that might be described as "heath", but decidedly not the whole area.

I now see that you have marked nearly all of the Caradon area as "heath" as well. Have you been there? There are a few patches that might be called heath, but not the while area.

Why have you changed Fore Down to heath? It is clearly a common, and is grassland. Did you not see the source tag indicating survey and local knowledge?

But asphalt is the default surface on roads in the UK. Why add redundant tags?

Correction. Sorry, I forgot that this was a straight deletion.

The place is empty and there is no reason to suppose that it will remain a food establishment.

I agree that the address is likely to remain the same. I doubt that I will bother to map it unless the new establishment is of some significance to users of the map.

I see no point in leaving it on the map while it is empty.

As I pass the place regularly, I will probably remap it when it is reoccupied if it is of interest.

I expect that the address is the same, but I doubt that the other information is unchanged.

I provided that original information, so have no problems in deleting it when I was not sure that it was still valid. I am more concerned with adding the food hygiene rating when I have time.

It was a very quick edit when I was short of time. I hope to refine the changes when I am less busy. I had been meaning to update the shops and so on for some time. There have been other changes that I know about, but have been too busy to grab gps records thus far.

Are you local?

You have added new roads that are not yet present. Please consult with local mappers before guessing about what is on the ground. This area has been regularly and carefully surveyed, and if the roads were there, they would have been mapped.

I have now looked at the OS Streetview. So I can see where the original came from. And it is just wrong!

As I have found from previous experience, that Streetview is so approximate (presumably OS do have accurate mapping, but they degrade it before making it open), that it is just too poor compared to reality. Or that is old mapping: water courses are fairly dynamic and the road building may have modified things a fair amount.
Until I walk the bank of the river with a gps, which is probably not feasible in most places, I can't be certain, but various portions of the river are clearly visible from the adjacent tracks, and it doesn't seem to match OS Streetview.

Why do you believe that OS open data is reliable? I have frequently found it to be inaccurate and frequently outdated.

I haven't looked at OS Opendata Streetview, as yet. But I know that area well and have surveyed it many times. That water= natural seemed to be just fiction. But that whole area is a complete nightmare which looks very like an old misguided attempt to tag for the renderer. And shared nodes makes cleaning up really tedious, even with tools. For example, the wood covers everything including the river. But there are weird bits of wood cut back around the river, and this fictional water body. I can only imagine this was an historic attempt to make the river stand out in some renderer where the contrast with the wood was not "good enough". I have spent far, far too long trying to clean up that mapping to make it match reality better. I will try and look at the Streetview, but previous experience suggests that it can be very inaccurate.

I think that as I have been on the ground with accurate gps in the last two days and many other times, I am in a much better position to say that this deletion is justified and improves the map. Spurious detail surely has no place in OSM.

Sorry. I should have checked the history properly. I see it goes back to another changeset by wh68. I was on site again maybe 10 metres away from the River a few hours ago. I can't see any point in this natural=water which is wildly inaccurate when the River itself is mapped. I am inclined simply to delete it, but am loathe to do that. But after consideration, I have now done just that.

The riverbanks around the East Looe River near High Wood including
osm.org/way/273443971
look ridiculous to me. I know the area well, and while one can't access that part of the river directly, it is not much more than a wide stream there. Maybe 3 metres wide, and typically only 50cm deep. The concrete channel under the road towards the south is only around 2 metres wide, and the river/stream is usually only a few cm deep. I was there 2 days ago.

I have now found way 170991577 and corrected that as well. Seems to be the only other case.

I have corrected the tag on way 170485030. Haven't found the other one as yet.

No idea how that happened: it was a long time ago. I am sure that it was not intentional. Maybe josm filled in a tag with some sort of default that I didn't notice.

I was surveying with a gps-equipped dashcam + a pretty accurate gps unit as an extra check. Mainly improving geometry as I recall. I have deleted the dashcam video (lack of storage capacity), so can't see whether I thought the roundabout had vanished. But if it had, I think that I would have remembered and probably added a note. So I think it is probably just a mistake. Feel free to correct it.

Hope that there aren't any more of these.