How decisive were missile weapons in battle?

[Sean Manning]

Paul B. wrote:

The role of lithoboloi should not be underplayed. Xenophon refers to rock throwing repeatedly, and off the top of my head, Thucydides wrote of them on both sides in battles between the Athenians and Syracusans. Hoplites too were known to throw rocks as improptu missile weapons. You don't even need to carry them in a place as rocky as Greece. If we can judge from vase depictions, even allowing exagerration, they were not "pebbles", but substantial rocks.

The reason I referred to 'pebbles' was because men on a horseshoe shaped hillside would have extreme difficulty throwing fist-sized 'rocks' over troops massed in the valley below, to reach Macedonian troops on the valley floor some distance away from the Phocians (not in close contact). Furthermore, there is no instance I know of in warfare in the Mediterranean world where an Army, or a heavy infantry force, panicked and ran from showers of hand-thrown stones......as we have seen, it was a common prelude to most battles.......

The morale effect of the noise of the machines and the rocks creating dozens of casualties (among thousands) was sufficient to panic even Philip's hard-bitten veterans.

But since this is an ambush, and the rock throwers are on hills, isn't that all speculative? Its not shocking that an army flees when its suddenly attacked from all sides by an enemy which it thought was beaten, whether the attackers have the latest high-tech equipment or stones and pointy sticks. Thrown stones would have plenty of range to outreach pikes. And for all we know (a few dozen words in a text centuries after the event it describes) the men at the sides of the valley could have been throwing 10 lb rocks by hand which bounced down the slopes into the Macedonian ranks. And there isn't much point in throwing 'pebbles' at armed men by hand. I don't have a horse in this race, but lets be clear what is speculation and what is a fact ...