How Effective were Spears Against Cavalry?

[Forty-One]

Marcus Junkelmann experimented with this and wrote a little report in the third volume of his "Die Reiter Roms". His conclusion was that you can actually train horses to run at, and to bully into, a formed up line of men shouting and waving pointy objects (they managed to get their horses to do it), but it takes an insane amount of training over a long time to get them to do so. I recall it took them several months. He thought it unlikely that any army would have had the time or inclination to train their horses to that extent. Certainly history seems to bear this conclusion out.

I recall once sitting in Peter Connolly's Roman saddle reconstruction on a wooden horse mockup while others surrounded me and attacked me with "spears" or tried to pull me onto the ground. I lasted about 3 seconds, not that I'm a trained cavalryman of course and the wooden horse wasn't exactly what you might call "frisky".