The Sliver Removal feature in Moldflow Insight accounts for any very high aspect ratio meshed areas, and corrects it when enabled. If it is disabled, they can be manually corrected through the Mesh Repair dialog, or they can be corrected automatically through the Mesh Repair Wizard.
For more information, go to:
ASMI Help > User's Guide > The Mesh > Mesh Repair > Dual Domain and Midplane Mesh Repair > Remove Slivers
Hope this helps!