Parthian/Sassanid heavy cavalry use bamboo lances?

[Condottiero Magno]

If the couched lance technique had been in use for many centuries by many different peoples how do you account for the superiority shown by the heavy cavalry of the Normans and other Westerners against Byzantium from the 1060s and against the Middle Eastern Muslim peoples from the First Crusade onwards? Please do not say armour, because Western armour at this time, though heavy, was not as diverse or effective as the armour used by their Byzantine and Muslim foes.

The Byzantine princess and historian Anna Comnena stated: "For a Frank on horseback is invincible, and would even make a hole in the walls of Babylon". Franks were obviously doing something that contemporary Byzantine cavalry were not.

Their mail was superior to that of their opponents and it covered more of the body. Their horses were larger and better trained for shock tactics.

"He furnished them abundantly with arrows and exhorted them not to use them sparingly, but to shoot at the horses rather than at the Franks. For he knew that the Franks were difficult to wound, or rather, practically invulnerable, thanks to their armoured coats of mail. Therefore he considered shooting at them useless and quite senseless. For the Frankish defensive arms is this coat of mail, ring woven into ring, and the iron fabric is such excellent iron that it repels arrows and keeps the wearer’s skin unhurt." [Alexiad, VIII.8]

Nothing to do with mail, which was also abundant in the East, along with other forms of armor. Other than a preference for stallions, there wasn't a difference in horse sizes, and anyone who'd read the manuals would note that the Romans employed superior shock tactics.

As for Alexios emphasizing shooting horses over riders, he'd have said something similar regarding enemy kataphraktoi and these would've had barded horses.

Alexios was in a position where he had to cobble together forces mostly consisting of crap, as the civil wars had depleted the treasury and experienced manpower was in short supply, mentioned in the Alexiad, plus he wasn't that great a general. At Dyrrhachium, those invincible Norman horsemen were impotent facing a phalanx of Varangians and if they hadn't over-extended themselves, Alexios wouldn't have had a reoccurring ulcer.

If I might ask, how much of the Alexiad have you read or are you just cut and pasting cherry-picked passages? The Alexiad is about as reliable as the Bible and shouldn't be taken at face value, unless one's a fundamentalist .