Unlike many other sites, sig lines on PerlMonks seems to be a simple pre-population of the edit box. The sig isn't a separate entity appended upon posting the node.

For example, I open my reply box, and I see my sig in it, and I can edit/delete my sig if I want, before posting. In fact, I include one crutch: a <code></code> pair just above my signature; if I don't want them for a code snippet in my replies, they're easier to delete than to type them when I want them.

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