If we look at the options of we have to conduct in combatives, as combatives in itself may be a mental option rather than a forced position, we find that we have some priority decisions to make upon engaging in a hand-to-hand or melee weaponry fight, engaging with a projectile weapon via anatomical and physiological adjustment or disengaging for the projectile weapon to have effect without being knocked off line to target.
Option One: disengage to regain projectile weapon range.
Option Two: gain a controlling position and utilize a secondary weapon.
Option Three: close the distance and gain control to finish the fight.
If we look at option one it would fit the setting of being door ambushed at grappling range by a melee character or someone with an inoperable firearm. The disengagement method may be to use the doorjamb to force the opponents arms and hands against to disconnect their hold on the projectile weapon. From this position you can pull it back into a position of which to engage, sometimes that being the close combat position as per the close combat drill.
If we look at option two you can easily weigh up that it is in a position within the room now, you have little option for disengaging; for instance you are jammed, one meter in the room and heading towards the threat in the hard corner. The solution is to utilize your secondary weapon; to utilize pistol then remember the 21 foot rule (which can be halved), for instance backpedaling... if you utilize a knife then you have to be the aggressor at this point and go in with violence of action as the playing card.
Multiple tactical problems occur to me, not only as it IS risky behavior but upon striking. How do you deal with body armor, webbing, a battle rig, a helmet and so forth? What are some good methods to counter those? You know it's a lot to think about. Not only this but when you get shot can you still operate? Probably, depending, but not as efficiently.

Option number three; to close with the enemy quite similar to option two but utilizing the weapon at closer range, to me that says use a closer range weapon or prepare for its use such as a melee weapon; a knife, a baton.

Another process of this is if you are disarmed or the action was blocked or negated to some effect. Where do you go next? The disengagement scheme begins to look more promising to mitigate those risks. Anyhow as with all these steps they should be used simply for time-gainers or potential life-saving actions for yourself until the rest of your team flood that room.
It always counts at this point to put yourself out of their arc of fire or get the combatant into it; then comes a multi-weapon engagement or multiple friendlies on this combatant thereby increasing your odds.
What are your thoughts?
For more reads and some reference use:
http://www.warriortalknews.com/2011/02/ ... fight.html
http://www.theppsc.org/Staff_Views/Tuel ... .Close.htm
http://www.warriortalknews.com/2010/08/ ... istol.html
"The knife is my 3rd weapon system on me. Rifle, pistol and knife. If I have to end up pulling it out, I want it to be big scary, brutal, and cause massive amounts of damage. Just my own style." - Tom Spooner, ex-CAG.