Slitherine

Situation:

Small unit of foot in extended line, in front of:

Unit of Foot (large but 3 ranks deep) + artillery (2 bases).

Can both units in behind move through the extended line as long as each can reach the halfway point of the extended line bases? Would both units, if necessary, push the extended line back a base width?

It seems like artillery in particular, but a 3 rank deep unit as well, could gain a fair bit of extra movement this way.

Yes.

The deep foot movng through the extended line could gain 3.5 base depths of additional movement max. If the area beyond was too small to move into then the push-back-up-to-1-base depth exception kicks in and it moves 2.5 beyond the front rank of the extended line.

The interpenetration approaches taken by many rules systems would tend to provide an ahistorical advantage to the linear system (i.e., Unreformed double Extended Lines) over the Reformed system of tactics and grand tactics because of the mechanical issues of depth and movement distances on the table. FoG(N) goes a way to neutralize this and the effect of the rule that the interpenetrated unit remain stationary for the entire movement phase, which is necessary to avoid abuse of interpenetration by leapfrogging.

We are trying to replicate or enable ( but not in exact move by move detail ) the manouvre that was termed " "passage of lines" which for example is covered in Marshal Ney's writing on grand tactical manouevres and his comments on the regulations of 1791 - George Nafziger covers this in some detail in "Imperial Bayonets" with three diagrams of alternative methods . According to Nafziger these were still being used in 1831.

The main thing is that it shows that large formations could do so without it being regarded as a cause of disruption and there was provision for doing so . With regard to lines and columns it is the intervals between and within Btns that make many of these sorts of things feasible. Watching the annual Queen's Birithday parade can give one some insight into how that kind of thing could work admittedly on a small and highly rehearsed scale.