Heavy cavalry charge:How exactly was it done?

[Paralus]

If this weapon in its eighteen foot length, in Markle's view, rendered the phalanx a cumbersome and fractious animal then such would also apply to charging cavalry in files as he imagines them.

Renaissance Polish hussars were known to use lances of this length to good effect. ( http://www.jasinski.co.uk/wojna/comp/comp06.htm )

Yes but those lances were hollow. As well a 'modern' saddle was used including stirrups (overrated or not). I'd see a solid cornel wood sarisa as a little more unwiedly - particularly with a sauroter.