here's something to chew on!
want some more tactical opinion?
in military tactics at section (or squad), and platoon level:
The infantrymen with standard rifles provide defense and eyes for the support weapons. the support weapons are in place to support the movement of lighter equiped infantry, and be put in ideal positions tofire from cover into the open.
lets talk 6' x 4' in real world terms. this is a small area of land. because of the time-frame of a 6 turn game could be an hour to 24hours? because you're not actually taking soo much time to decide where those guys are gonna move and if a machine gun only gets 3 bursts off (heavy bolter?) it's a very quick snippet of time compared to real time fighting.
section commanders and platoon commanders (i'm talking NCMs here) know that they must keep thier support weapons up and running and do what they can to get them sited in a position which will allow them to fire from cover into the open with broad arcs of fire visible.
moving a support weapon in a firefight to the extent of needing to prepare its next position (like losing a turn of shooting to relocate a heavy weapon in game turns) means the section loses from 25 to 50% of it's firepower. in the firefight when the current operator of a support weapon isn't doing his job, the section commander gets a bit angry.
example: section of 10 troops with M-16 variants and 2 American M249 SAWs (Canadian C-9 LMG). when enemy contact is established, and the mission dictates fighting through. the section commander must quickly decide weather to allow his section support to stay and fire from thier position while the other 3 fire teams in the section advance OR have the support weapons take bounds with the rest of the section. if there's a problem and one of the support weapons go down. 25% of firepower gone. the second one goes down.. tht's 50% of the efective firepower. if a squad of 10 guardsmen with a heavy bolter move they've lost up to 50% of thier firepower or more depending on what they shoot at(or could have shot at if stationary) in that turn.. like lasguns shooting at really high toughness?.....
before i get anymore in depth to cover and movement or go into smaller group to team combat in urban terrain.. platoon level attack..so on and so on....boring...
one of the biggest reasons for using the support squads attached to the HQ is freeing up troops to advance with covering fire. a squad of 10 guardsmen with a special weapon and no heavy weapon can constantly move wihtout losing shots while support squads or other support elements fire on enemy positions without losing shooting phases due to movement.
if you have an army that likes to move a lot then support weapons in some 10 man squads are good since you need to move those guys into cover which they will use to give them protection while setting up where others in your army can't see or reach the same arcs of fire.
i wouldn't recommend moving support squads unless they won't be likely to see a proper target for 2 turns.
deployment is critical. think arcs and lanes when you deploy or move heavy weapons in support, command or even 10man line squads.
if there is a decent sized building with forest blocking most of it's view toward the enemy deployment zone... you may not want to jam suppot weapons into it. it can be more tactically sound to site support weapons in forest cover if that forest has better arcs and lanes of fire. think kill-zones.
ideally the supprot weapon should be placed in a terrain feature in a position which allows it LOS in direction of possible enemy approach. also, the LOS should be close to max range before looking at terrain features which the enemy can use for cover or concealment. *site in cover and fire into the open* and don't forget about being able to fire at differnet arcs without movement. if the enemy can reach the support weapons have infantry with special weapons or storm troopers or something that can protect the valued support weapons from assault. support weapons reach out and touch the enmy while protecting regular troops and the regular troops protect the support weapons.
and then there's mortars. in 1700pts i like to take 8. 2 squads of mortar support squad and a mortar in each of 2 command squads/ they are great for taking out infantry belive it or not. they can pin. they are pretty cheap for not requiring LOS and staying behind a terrain feature all game. mortars have been key weapons in many games i've played. mortar support can make your enemy keep his head down or force him to move to you. mortars are great at redceing the firepower an enemy can sit and dish out to you. oh yeah. i also use 1 to 2 bassies... but that's another thread
though i am big advocate of support squads.. you have to be wary of all eggs in one basket situations. you don't want to loose all your effective anti-tank because one lascannon support squad got wounded to the last man and your missile launchers are fallingback due to modified ld tests