I am often asked how and why men enter the close-packed formation needed to conduct the othsimos as I define it. Here is a little video by some reenactors showing how to breach a shield wall. Note the lengths they go to to keep their men packed belly to back. If Hoplites conducted short terminal charges directly into othismos- as opposed to long running charges straight into othismos, which I doubt- then this is how the men packed. Only by packing tight can you transfer your aggregate force. These guys in fact charge too far, since any distance past that needed to achieve their "ramming" speed is wasted. Because close order is more important than velocity, this can be done from very close range after a period of spear fencing as well as from the opeing of combat.
The only way to resist men in this formation is to match it. A dense, close-packed phalanx will simply absorb this. Multiply this interaction along the front of a unit within the phalanx and you can see how it occurred.