Even though I understand why something like #2014 wasn't and won't be implemented, I would like to propose that the administrative boundary layer be hidden by default rather on the basis of its usefulness as a feature in the overall context of the editor. I understand the arguments underpinning the decisions to close such tickets, but in practice 99% of the times I use iD, administrative boundaries just get in the way of my editing experience, and I can't imagine that if I were to, wanted to or had to work with admin boundaries, iD would be my editor choice.
What I do see quite often are roads intersecting admin boundaries because the editor gladly snaps the two together. In fact, given the "magnetic" way in which iD makes this happen, as a new user, I would think that they _want_ to be snapped together and, more importantly, that they _ought_ to be snapped together since it doesn't distinguish boundaries to highways when doing so.
Where the boundary is over a road (as is often the case in the US and I would imagine elsewhere), I often run into users using the unglue tool _on the whole way_, which results in long stretches of important (i.e. primary, secondary or tertiary) roads being disconnected entirely from the network (and fixing them in iD is a nightmare _precisely_ because of the presence of the admin boundary at the same location as the road in combination with the snapping functionality).
Clearly admin boundaries _underlie_ any highway or feature layer, but as no such concept exists in the editor, I think it best to disable the layer on the basis that it's seldom useful to have it on in iD. It can always be turned on, because yes, no such restriction should exist for users, new or old.
PS: By _hidden_ I mean, more specifically, that the _Boundaries_ checkbox be unchecked by default under Map Data > Map Features. If you want it on all the time, the editor could remember your choice for your next visit.
I can also see this being useful for census polygons in the US.
We discussed in #2942, and at the time there wasn't enough interest to actually change what iD does, but I'm open to hiding the admin boundaries if that's what people prefer.
I did this
I did this
@bhousel This is great, but now the text is wrong when disabled:

That screenshot is what it shows when the map is zoomed out (zoom < 16).
Can you check on http://preview.ideditor.com/master/ and see how it looks at both low and high zoom?
It should work like before, but with "Boundaries" unchecked by default until the user checks the box.
Sorry, this was the wrong issue, I was talking about https://github.com/openstreetmap/iD/commit/5a8709bc67c7b9e8db9b2b39bf94f6b78634efa6
We should have it say something different when the OpenStreetMap data box is unticked.
We should have it say something different when the OpenStreetMap data box is unticked.
Oh gotcha - yeah I agree..
It says this now:

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