What the description of Sphacteria has to tell us

[Paullus Scipio]

I think you may well be on to something with this idea ! If what we know about Spartan drill is correct, in open/normal order they would usually form up on a front of 30 x 12, which would give a front of 60 yards x 12 ranks deep - but this would be a very narrow front, and doesn't sound right....but the Athenian phalanx, if a typical formation was adopted 8 deep, would be on a front of 200 yards (800 Hoplites 8 deep, 6 feet per man frontage).

My hunch is that the Spartan would have halved their depth to match, and so be on a front of at least 120 yards still in open order, and perhaps hope to leave the Athenian left flank 'hanging in the air' at contact - 60 man front x 6 ranks deep in open order, a front of at least 120 yards. We know that the terrain was burnt out scrub, that the Spartans couldn't even block the narrowest part of the island (500 metres), and so were exposed to fire from both flanks (Thuc IV.34) and that visibility was poor, ( so undoubtedly one end of the line - whether 60 or 120 yards - was not visible to the other), not just because of the burnt out scrub but because " great clouds of dust rose from the ashes....it became impossible to see in front of one" (Thuc IV.34).

The skirmishing went on "for some time".

" Finally, after many of them had been wounded, penned in as they were and unable to move freely, they closed ranks and fell back to the fort..."
Suppose they moved to close order, 120 yards long or more in the burnt scrub but only 3 deep, and then realised their line had ragged holes where maybe whole files of three were missing - at that point, like the french grenadiers, they realise the extent of their losses and that they are too weak to attack ( and should still be between 50 and 100 yards from the motionless Athenian line, under constant fire from front and both flanks)....and at that critical point their morale gives way, or their commander realises the futility of continuing to attack ( after all, as the charge went in the flanking psiloi and peltasts must inevitably find themselves in the Spartan rear, and act accordingly )

All pretty plausible... considering that 148 from 440 Hoplites were killed (over one-third!) and almost all these will have become wounded/killed in the open skirmishing " for some time" and the subsequent retreat to the fort....
A laus for your perspicacious insight ! D