[Nurse - the screens...]
From my recent playtesting game with Ian, we ended up with a note of about 12-14 points in the rules which needed some change - or at the very least some reconsideration. Well and good. That is what the game was about (apart from the social delights), and it had gone well enough to encourage me to get on with thinking about what, if anything, needs to be done.
One area of the rules with which we had some problems (i.e. for which we found we were making things up as we went along, to cover holes and clunky bits) was that of interpenetration. I realise that this gets us into all sorts of disagreements about definitions, so I shall skip lightly over that, and also I shall continue to avoid reading drill manuals, other than the references summarised in the works of Chandler and Nosworthy.
By interpenetration (which is a vague word, but I hung on to it because it affords me some adolescent amusement), I am broadly covering the matter of troops passing through their friends, and in two situations:
(Type 1) voluntarily moving through friends as part of ordered movement
(Type 2) moving round, through (or over) friendly troops when retiring or routing
Since plagiarism is the most sincere demonstration of respect (which is why I am pleased to be so widely respected on TMP), I did a lot of reading, especially of prominent rule sets, some for periods which were not entirely relevant. I looked at, among other sources:
Beneath the Lily Banners
Piquet's Field of Battle (3rd edition)
Black Powder
The Twilight of the Sun King
Polemos's Obstinate and Bloody Battle
Honours of War
Charles S Grant's updates to The War Game Rules
and I got a lot of useful information online - in particular from the excellent Rod's Wargaming blog. I also revisited For King & Parliament, and I have the rules for Tricorne, which is the AWI member of the Commands & Colors family.
A lot of excellent stuff here - some of it made more or less suitable for my purposes by the underlying game scales, but all of it the product of very sound reasoning. Impressive.
The thing which surprises me is the frequency with which these experts appear to disagree about how such things worked, and even the extent to which they did work. I am not going to produce a table of differences or anything, but the view seems to range from units being able to move freely through each other without delay or disruption (provided they have sufficient movement allowance to get clear of each other) to much more restrictive approaches.
In particular, Field of Battle's basic approach to the topic of Type 1 (voluntary) interpenetration is very detailed and pretty liberal, and I always take very seriously the way the Piquet games are thought through and researched, but in the period-specific section for the WSS it says that such voluntary movement is not permitted, except through deployed artillery batteries. This came as a bit of a surprise, and further reading got me into online debates about whether there should even be such leniency towards moving through artillery - a couple of writers expressed strong views that batteries took up more room than is normally assumed, and that the idea they were mostly space is incorrect because of the crowd of support wagons and limbers, not to mention people racing about with ammunition. I suspend judgement on the porous nature of artillery, then - for the moment. There are a lot of very earnest people out there. Bless them all.
I'm somewhere at the start of a dialogue with Ian about what we learned and what he thinks of my thoughts for changes, plus ideas of his own, etc, so none of what follows is intended to pre-empt any of that discussion, but I'm sketching out some thoughts - mostly prompted by the wide range of opinions elsewhere. I must also emphasise that my priority is to produce a game which is enjoyable and which runs without hitches, rather than to reflect the inspired detail of military thinking at the start of the 18th Century, but it must bear some resemblance to what really happened!
It seems to me, after all this private study, that the fundamental principle of military theory at the time was to prevent the enemy's lethal units of Horse getting around your flank, or breaking through any gaps in your line. Squares were almost unheard of, except in odd instances where a single unit might be isolated somewhere, so the ideal was an unbroken line, from horizon to horizon, the only discontinuities being strong terrain features or built-up areas. The second line of units might have intervals, but never the first; it was an established fact that cavalry could not defeat formed musket infantry attacked from the front, so give them nothing but front to attack.
This means, I think, that the spaces between units which I have claimed, in other periods, give room for routers or reinforcers to pass through were virtually non-existent.
Early days yet, and this is a sketch, but I'm thinking along the following lines for the Type 1 (voluntary) interpenetration situations (note that my game uses hexes, but the principles should hold good in any event):
* Friendly (march) columns and limbered artillery may move freely through or past each other, and any troops at all may pass through friendly unlimbered artillery, but in both these cases they must have enough movement allowance to avoid ending up in the same hex, and may not come into contact with the enemy while so doing.
* Friendly lines which are adjacent, parallel and either one behind the other or directly facing each other, if both are given orders to do so, may exchange places, provided neither of them is in contact with the enemy at any point of the manoeuvre.
And that might be about it for Type 1.
Type 2 needs some more detailed thought. Despite its pretty strict view of Type 1 interpenetration in the WSS, Field of Battle allows routers to pass through (leapfrog) anyone behind them, there seems no limit to how far they can jump, but they have to keep going until they are clear of the rearmost. I'm not keen on that at all, not in a system of units with no gaps in between.
Ian and I prefer a version where retreating units may push a single unit back, without upset to either party, but if this is not possible without pushing back a second unit, or if impassable terrain (or the enemy) gets in the way, then they have to take any extent of the required retreat which they are unable to comply with as losses. Yes, this is very like Commands and Colors - well spotted!
I'm still reading and thinking - any helpful ideas will be very welcome - any prepared lectures on the full procedure for Passage of Lines will be less warmly greeted - I've done a bit of that this week!