Standard frontage allotted to a single legionary?

[Sean Manning]

Robert, are you sure? Round and oblong shields are rarely wider than 90 cm, so normally if you have significant overlap between shields you are closer than 2 cubits per file. (Incidentally, that translation of Vegetius has a misprint; he says that one thousand six hundred and sixty six men fit into a mile. One Roman mile is 5,000 Roman feet, and 3 x 1666 = 4998).

I'm not sure if I agree that shields, in general, are designed to overlap; do you mean late Roman shields?

Of course these numbers are approximate- soldiers probably measured the right space by eye and by using their arms as two-cubit measure- but they work as rules of thumb.