DJ's optimizer might
be able to automatically remove the nubbins.
The optimizer as its included with the stock PCB version 20060822 is
pretty good at removing these nubs. I autorouted a board the other day
and there was only one nubbin that wouldn't go away with the optimizers.
Apart from three hi current traces I routed by hand using polygons,
correcting this nubbin that the autorouter failed to remove was the only
manual routing I had to do on this particular board (80 thru hole
components).