well i specifically speak about the lance breaking, also theres context reason why the lance break, like “armored cavalry against armored cavalry charge” and around napoleonic era it less occurring though. and i did mention it likely to stuck on opponent.
i dont know how much speed needed but in that video you dont really need to be so fast.
regarding dropping the lance i agree but it less likely to over thrust for the battle or war type lance, since they are less tapered and pretty huge, nonriding opponent likely get knock back rather than being thrust through, and theres also jousting lance that was blunt and broad and that joust type are not mean to break even against cavalry (cant found the image so far, its the one where they wear a big broad helm, the one that showed in dark soul and look like onion, it was mean to prevent the person breaking their neck upon impact by this lance)
oh yeah regarding wrist breaking or injured the shoulder i think that exaggerated since most proper form use the forearm and armpit support, including lance rest to help lessen the weight a bit and give easier control to change lance direction, theres also lance technique that only using the armpit entirely so far i dont found the image though, but i found this instead. so yeah nothing stop lancer to use both hand and i think this can help answer the problem of lifting their lanced victim up, outside of the help of the foot which is one of a way for knight to lift and keep their lance upward.
also here found the one that clearly show it only use the armpit.
also here some copy paste from one of the link in the forum regarding lance rest and grapper
Better couching ability led to increased armor. (Also influenced by better archery.) The increase in armor led to the development of heavier lances. Heavier lances and improved archery led to the development of plate armor. It is difficult to “couch/clench” the lance in the armpit with armored rerebrace and breastplate. The shock of impact tends to push the lance backwards under the arm. This led to the development of the lance rest and grapper. The lance rest took the weight of the lance and along with a grapper or “stop” on the lance, allowed for the impact to be translated more directly to the breastplate and therefore the torso.
With the leather or steel grapper ring on the back of the lance, the weight of the lance and force of the impact was no longer focused on the hand. The lance rest and grapper led to the development of still heavier lances.
regarding the spear technique, yep, but theres also the horse speed there though, i am not only speak about lance charge though theres other horse technique other than jousting after all.
regarding attaching the lance to motorcycle wont that end up knock or lift up the motorcycle upon impact though? because the lance gonna bend or springing a bit when it hit unless it short.