Sarissas and a phalanx' front line

[ziegenpeter]

Hi fellow EB-fans!
I wonder if pike using formations, such as the diadochoi's main forces, when facing non pike enemies marched closer to them as they would when fighting other pike formations.
This would allow the first lines to attack enemies in the backlines while the pike backlines attack and hold off the enemies frontlines. I drew this beautiful pic, I hope it underlines my description