Rather than claim to know what's common, here's what I do:
I drop the mirrored warning page into a new folder, without any erroneous numbers - keywords are better for everyone anyway. This way the warning page is always an index file. Some LLs like this, other's don't really care. Personally, I like it, because I can.
If I have the time/energy, I'll mix things up a bit on the warning page on preferred mirrors, so there's not quite so much "duplicate content".
That's pretty much it for me, I think.
Btw, I submit to a lot of lists, and I get accepted by a lot of lists.
I wish I could say all, but I often add new lists to the mix, so sometimes I just don't know who is or is not active and who likes/dislikes my sites.
