gEDA-user: dead copper removal

[DJ Delorie]

> The clearances can be "tweaked" while observing them using the check
> polygons setting.

Good point.

> There is a danger to morphing and directly exporting a gerber
> however: A restored region could intersect multiple "joined" line
> and thus cause a change in the topology.

So... it's safe only if you know the join flags are correct for all
the lines, not just the ones that happen to intersect the main part of
the polygon?