[Tagging] Layer=* tags disappearing

[Peter Budny]

I've noticed that some bridges and tunnels I've edited previously no
longer have layer=* tags on them.  I could swear they did before.  Is
there some bot (or person) going through and removing them?

I thought that setting bridge=yes or tunnel=yes didn't imply anything
about the layer.  The wiki says, "it is better to explicitly state the
layer".  It definitely appears that the renderers don't get the layering
right without explicit tagging.

For reference, I'm looking at http://www.openstreetmap.org/?lat=33.89221&
lon=-84.45676&zoom=17&layers=O (which I just fixed)
-- 
Peter Budny  \
Georgia Tech  \
CS PhD student \