Some - if not most - of the large "sarisa" heads are likely hunting points (much damage, close range). This would include the point "rusted" to the wall at a height nowhere near that of a sarisa. Connolly is correct about the size of the points: as Sekunda too has remarked. Thinner for length points penetrate far more easily and the literary evidence clearly shows the capability of sarisa points in this regard.
Kleomoenes eveidently constructed some 4,000 apsides with a porpax he then instructed his troops not to use so as to hold the sarisa? Philopoemen - a general with wide experience - seems to have not understood this point. He re-armed his troops with both the "Argolic" aspis and the sarisa.* A shield larger than 70 cm diameter cannot be used in conjunction with a 'sarissa', and Connolly considers the Getty museum example ( at around 80 cm diameter) to be a cavalry shield. All the other surviving examples are less then 75 cm. Similarly, a 'rimmed' aspis shield cannot be used because the rim prevents the fore-hand in the antilabe from grasping the 'sarissa'.
A reading from the gospels according to Asclepiodotus, Arrian, Aelian or Onasander: the cannonical books of the Church of Greek Tactical Law. Written well after the event and very much representing an "idealised" world of the phalanx. Enough of my irreverent sarcasm....* The 'synaspismos' formation, with one cubit (18 inches/45 cm) frontage per man was perfectly practicable, and could easily be formed by 'doubling' the file from 'close' formation, just as the Hellenistic manual says, but that marching and charging in this formation was all but impossible, again as the manual says...
That the phalanx formed "synaspismos" by doubling up (file insertion) is not at all likely. Indeed it is far more likely that it did so by actually closing down the gap: yes, shortening frontage (heresey to Xenophon I'm well aware). Polybius (12.21.1-4), in the midst of a spleenetic harrangue over Kallisthenes' historical innacurrancies, plainly states this to be the case:
Polybius has worked out that the number of men in Alexander's army - eight deep in "close order" - occupy forty stades of width. He then clearly states that were these men to take up "shield to shield" (synaspismos) order they would halve their width (but still not fit on the fourteen stade plain.But the greatest blunder is still to come. "As soon as Alexander," he says, "was within distance of the enemy he caused his men to take up order eight deep," which would have necessitated ground forty stades wide for the length of the line; and even had they, to use the poet's expression, "laid shield to shield and on each other leaned," still ground twenty stades wide would have been wanted, while he himself says that it was less than fourteen.
Plainly Polybius believed that Alexander's phalanx did not "double up" (that is, insert the rear four - or eight - files) to make synaspismos. Had it done so - becoming only four deep - it will have occupied the self same 40 stades. Clearly, in Polybius' view, Alexander's phalanx did not operate with the confines of an idealised and mathematically perfect world and formed "shield to shield" (if nothing else) by simply closing up files.
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