That's more looks like joke than suggestion, so your proposal is to sit on the ass all the first phase and waiting on the german rocket arty, panthers and 2 star fighters lol. And actually if you not going forwards with your tanks you will die soon from enemy infantry which comes for you and from enemy mortars. And as I said before Sextons dont do a lot of damage.
Obviously you adapt strategy to opponent (vs Lehr you push) but generally the infinite avail, income curve, and access to early mediums/AEC lets you slowly push the entire frontline at once in different areas. This isn't a deck for making an armored fist, it's a deck for slowly advancing across the entire map.