Not true, very few made it ashore on the one of the US beaches, lots made it ashore on other beaches. The canadians used them very effectively.
As I understand it, on Omaha the navy ordered them launched way to far out.
They were used on the Rhine, in Italy on the PO in the invasion of southern France.
It would actually be a good addition to the game. It it wasn't so vulnerable to 303 mg fire.