Well Mike, seeing as you are asking!
In my experience, midfield players have to be; a)combative, not only in tackling opponents but also in..... b) harrasing opponents even when drawn a bit out of position and.....c) be highly mobile in covering virtually every blade of grass on the pitch.
A winning team will 'command' the midfield, if they don't then the team is going to get pressured constantly in defence and it is only a matter of time/statistics before they succumb and cocede goals. Our midfield seem to me to play too deep and give the midfield away too much. A 4-4-2 formation is often talked about, and yes, you are correct in stating that a formation is a mobile device. eg. When attacking it becomes a 2-4-4 (in its simplest form and variation). Managers often talk about having a 'strong spine' in a winning team....a good strong goalkeeper...two strong central defenders, who don't need to roam about too much except to add weight at attacking free kicks and corners....two forwards who have the 'knack' of poaching goals...but most importantly two central midfielders who run the whole show and should cover more ground than the the other players, eg George Boyd at Burnley who records the most kilometers covered virtually every time he plays!
Earlier this season we seemed to be trying to play a '4-4-2' formation but it seemed to me to be more like a 'square' layout of players with a hole in the middle. More recently with the 3 central defenders and wing backs it has looked like a 'circlular' layout but has still had a hole in the middle! Somehow we need to pick players, or coach them how, to fill that hole, to contribute in an attacking way as well as in defence and then we might have a chance of dominating opponents and take the pressure off our central defenders. Rememeber Coley thinks that this is the best defence that he has worked with, yet we have given more goals away this season than virtually all of the teams in all divisions!
When the team is defending, the midfield players have to be able to 'slot into' the penalty box but be ready to break out quickly. When attacking they have to get quickly up the field in support of the centre forward and even get down the wings themselves in the role of a 'winger'. They should also be capable of scoring goals from shots hit from outside the penalty box and be able to poach goals when they are in the box, thus getting 7 or 8 themselves in a season. How many have our midfield scored this season?
I hope that this clarifies my tactical approach. Of course you need 'quality' players to be able to achieve this and Stanley are always going to struggle to achieve this when most of the players that we sign have struggled to maintain a place at other clubs.
It is wonderful to be a Stanley supporter and to have to fight against all the odds and not be a Man Utd or City or Chelsea fan and just have 'amazing' players bought at the drop of a hat!
Long live the survival of clubs like ours who year in and year out defy the odds!
ON STANLEY ON WITH JIMMY AND JOHN