The fact that your dad led a rifle platoon tells me that he was either a senior enlisted or a junior officer...and in either case, he would not have been party to the discussions among flag officers and political leaders as to where to attack and when.

And if you're confused as to the point of the article, if I didn't make it clear enough, then that is my fault as a writer...but the point is, the reason we invaded Normandy when we did was to (1) as much as possible, let both the Red Army and the Wehrmacht bleed each other dry (see the quote by Truman) and (2) when it was obvious the Red Army would be triumphant, to invade and prevent the Soviets from taking all of western Europe.