<VV> re: How does "cleaning up" a chip "remove any stress raisers?

[Kinzelman, Andy]

Joe,
When the edge of the glass breaks, there are lots of sharp edges inside the chip.  These are known as stress raisers, because they cause a weak area where any strain in the parent material can easily propagate.  For example, if you get a tear in sheet metal - you can drill a hole at the end of the tear; this will minimize the tendency for the tear to spread.  Likewise, if there is a small crack in your windshield, you can halt its growth by drilling a hole at it's end.
Now, back to the chip.  If you take and sand out the sharp edges of the chip - it is much less likely to grow a crack.
I may have misspoke, however, about the emery paper.  Tom Silvey correctly identified the proper sanding material; silicon carbide - preferably mounted to a cloth.  Check at a local glass shop for this - although it's possible that you could find it at a FLAPS, or hardware store.
Andy K.