I see op fire as being essential, but it needs to be seen as integrated within the available actions in a given turn, so that everything has it’s ‘minutes’ occupied to the same degree. If you op fire, you should not be available to fire in the direct fire phase. i.e. you can only lay down so much fire in the same time frame.
Some weapons need to be seen in the op fire role anyway, such as machine guns and anti-tank guns. Their role was to have interlocking fire zones and so op fire should not be a ‘bolt on’ rule to what else the rules can do, but fully integrated from the outset.
Op fire is also a good rule to link with intensive fire or desperation fire or whatever term is used for that ‘urgent’ fire that will test the training of the crews.
In terms of what is closer and presents the greater danger, under some threats an op firing unit might be more inclined to bug out rather than do what the wargamer wants:-)
Equally, you don’t want gamers able to mask their good stuff by putting weaker things in front that would draw fire by default.
If you take your example further, and swap out the Tiger fior an A/T gun, what if the distant tank was side on and a really good shot to take, too good to be true! but the M8 is closer and a danger to you – what kicks in, the best shot (best bang for buck) or self preservation from the fast firing, mobile M8? Is that a training / skill / morale division in thinking / action or is a single default, catch all rule overall the best option. The gamer should not be able to say ‘losing my A/T gun is worth it to take that tank out’ because that is unlikely what the crew is thinking or saying. A default general rule would not deal with your Tiger AND my A/T gun situation in an equally fair manner.
Effective suppression rules can be tied in to how effective op fire is
Aimed, deliberate fire is what it is and anyone can do it to varying degrees of competence, but op fire, depending upon environment can be subject to fleeting glimpses and fast reactions and good training and weapon familiarity.
A state of ‘cautious movement’ indicating the best use of cover, could be used to negate the effectiveness of op fire.
Should there be two types of op fire – cool and measured op fire, the sort that comes from an ambush and frantic panic op fire, the sort that is ….. well opposite to cool and measured 🙂