And although I do not recommend forming a large number of divisions ...
Nikolaos Kanellopoulos. The Byzantine Influence on the Military Writings of Theodore I Palaiologos, Marquis of Montferrat // A military history of the Mediterranean Sea: aspects of war, diplomacy and military elites. 2018
Английский перевод фрагмента из военного трактата Феодора Палеолога.
In 1326 he wrote a treatise with the view to advising the Byzantines on how to confront the empire’s enemies. Originally written in Greek and translated by Theodore himself into Latin, it has come to us via a late fourteenth century French translation.
Текст.
And although I do not recommend forming a large number of divisions (batailles), occasionally some people use large numbers of divisions, so hoping to menace and frighten their enemies. But if the enemies are prudent and experienced in matters of war then it is possible to overthrow and put in flight our troops because they will be better ordered to face the attack. So, in my opinion, it is sufficient to have three well positioned and well-ordered divisions; the first division must consist of the best and bravest men who are well equipped, ride the best horses and are experienced in the usage of weapons. The ruler or the head of the army should stand with the second division that is placed behind the first at the distance of a crossbow range; and a shorter distance could be harmful. The third division should be placed on the flank of the second. And if our infantry is not available, the third division should be placed on the left flank of the second, with the purpose that when the first division charges and attacks the opponent and the fighting becomes fierce and then without delay the second division comes to support the first and if the mêlée grows, then the third division should be mixed with the first and the second and attack the right flank of the enemy; because an attack on the enemy flank causes more damage, especially if this unprotected flank (i.e. by a shield) is exposed. In this manner all divisions are gathered together and fight the enemy. And if there are more than three divisions (batailles), let’s assume four or more, I cannot see how they can be properly organized to fight with their enemies. And they fight much better when they are all grouped together; it is advantageous to be grouped together than divided in many parts as we will show immediately with an example taken from Nature: when a river flow is divided into several parts, outside of the main watercourse, one may more easily cross the divided flow by fords than the united one, because when the river flow is united without being separated, the people cannot cross or ford; it’s the same when the divisions are teamed up together.
And if 1000 horsemen are available, 300 should form the first battalion and 200 the second one placed on the left flank and the third battalion is formed by the remaining 500 horsemen with the ruler at their head in order to support the other two. No horseman should stand outside the batailles and they should have units under banners known to all, in order to prevent interfering with each other when they are in mêlée. And for the footsoldiers with the rest of the army follow after the horsemen - those who are not hommes d’armes (i.e fully equipped knights) - having a banner is of no lesser importance, since this sometimes may discourage the opponent. And arrange your men in this way, depending on the soldiers you have. And if you have footsoldiers recruited from the common people, place them under command of some knights to encourage them during the battle. And if, as has been said, they are placed on the left flank and especially if they are armed with bows, crossbows and javelins and keep shooting on the enemy right flank and cause injuries and kill them and their horses, then at the peak of the battle they can provide relief and support (to the mounted men) and achieve superiority over the enemy that will lead to the victory. But, the knights I mentioned earlier, if you have a lot of them, do not place them on the left flank, but I advise you to arrange them in front of the right flank, i.e. in front of the second battalion of knights, so at some point they can participate into the fight. And thus the easiest victory can be achieved. The ‘force multiplier’ of those who fight valiantly together truly demonstrates that it is possible to have the victory without large numbers of fighting men, and in this way: if the first battalion collapses, the second one follows in the disaster and so everyone lose heart and takes flight. And so it happens like lances, because when in danger, one is no use, who cannot destroy it? But when two or three can be put and bound together, no human strength can tear them apart.
Занятно - хотя ударной является первая баталия, ранее нигде не встречал указаний на преимущественный охват противника левым флангом. При этом логика у "ударного правого фланга" ровно такая же - "крайние справа воины не прикрыты щитами, поэтому правый фланг должен быть атакующим". Вариант - "стрелять в левую сторону легче и удобнее, поэтому атаковать должен правый фланг".
С другой стороны - когда есть значительное количество пехоты, то ее ставят как раз на левом фланге, а третья баталия конных встает на правом. И строй приобретает "классическую форму"...
P.S. Вообще же весь сборник, на который указал уважаемый М. Нечитайлов, весьма интересен. Есть статья про Иоанна Кантакузина и еще много чего.