pothos.org

According to this theory these Hoplites were not the usual type of Greek heavy infantry but a new lighter type that had emerged after Iphicrates reforms. The big "Hoplon" shield was replaced by a lighter one and the spear grew bigger. Thus they were not able to fight in the frond line.Read this:Hoplites, when well-trained and experienced, were formidable soldiers, and proved many times to be the match for even Macedonian heavy infantry. Two examples will suffice, others can be found: The Thebans in 335 BC, despite being considerably outnumbered, had the better of the Macedonians until Alexander commited his fresh reserve of footguards,19 while part of Daraios' Greek hoplite phalanx at Issos managed kill no less than 120 Macedonian officers before marching off the battlefield in good order as the rest of the Persian army was routed.I have no doubt that if Alexander had sufficient numbers of such troops in his army he would have used them in an aggressive manner. Instead he used his mercenaries in the rear line.21 As Iphikratean hoplites, their long spears meant they could easily hold off Persian cavalry; had they been in the front line they would be very vulnerable to the other troop type the Persians disposed large numbers of: archers and other missile-men. Traditional hoplites had large shields covering their bodies, and greaves to protect their legs. Alexander's phalangites had smaller shields, but unlike Philip's orginal phalangites had acquired body armour, the thorax, in compensation,22 and additionally derived some protection from the forest of pikes sloping over their heads.23 Iphikratean hoplites would have none of these defensive benefits, and so could be expected to take heavy casualties from archery if they were to be positioned in the front line; being in the second line, their most likely opponents would be cavalry outflanking the main formation, as happened at Gaugamela. Alexander's tactical dispositions are entirely sensible if these considerations are taken into account; it is hard to reconcile them if most of his Greek mercenaries were either traditional hoplites or traditional peltasts. Full text: http://www.ne.jp/asahi/luke/ueda-sarson ... ates1.html

Sorry yannis this theory is tosh of the first order. There is next to no evidence for these so-called Iphaticrean hoplites, though his reforms are mentioned by Diodoros and Nepos there is no indication they were adopted by any but the troops under his command. Also these men were used inthe frontline against normal hoplites! The author of this piece is clearly mistaken; Alexander's hoplites do not figure in the frontline because they were politically unreliable, they were hostages as much as reinforcements and the mercenaries were in the frontline at all the battles and were peltasts.