Normandy US OOB errors

[Bioman]

I was just reading a book about the Normandy invasion and found that 2 regiments of the US 2nd Infantry division arrived on Omaha beach on June 7. They were in combat on June 9 near Trevieres without any heavy equipment or artillery support. In the game the division does not arrive until June 12 although their division artillery arrives on June 7.

I wonder if this is an error or a planned move by the developers to make it harder for the Allies to win. I know that casualty figures have been dumbed way down for both sides not only for this game but for the entire series. All you have to read is accounts about how devastating naval gunfire was compared to how ineffective it is in this game to see what I mean.