Happened to me last winter with my old Forester, Nationwide windscreens did a god job with the glass but botched up the trim on the right side of the screen. Lost said trim on A1M just south of Stevenage. Crack propagated from a small stone chip across the bottom of the screen interesting to watch it grow. Glad for laminated screens as the older toughened screen would have shattered leaving the car full of glass and vulnerable to the local lowlife scum.