There is often an objection to using cards for this purpose, and it goes something like this: "I don't like how much luck is involved with the card draws and being in the position were you don't have a card to make the play you want." On the other hand, a common objection to using dice for randomization/chaos is that the dice can interrupt a solid plan: "It took effort to set up my situation the way I wanted it and now that I've got a virtually guaranteed success the dice screw me over." Both objections tend to reach a conclusion of "that's not realistic".
In fact, both are right and both are wrong. Both methods have their problems, but they also introduce realistic chaos. I spoke with a military guy who was familiar with major logistical matters during some pretty serious combat. This guy saw how supplies, vehicles, personnel (a LOT of stuff, from many different places) got to where they needed to be when they needed to be there. Keep in mind, this is about putting pieces in place during a live combat situation. He summarized the chaos game mechanisms like this:
Either method is pretty realistic. Will the missile fire when you press the button? You don't know - you don't know if the maintenance guys showed up to work the day that missile was supposed to be checked. If it does fire, will it go where it's supposed to? You don't know. If the missile does get to where it's supposed to, will it detonate at the appropriate time? You don't know. There are any number of things that can go wrong - because we don't live in a world where everything always works as it should. Human error and mechanical failure are always possible.
I would explain this using a flat tire analogy. Moving an armored vehicle from one location to a combat situation could encounter any number of problems. Perhaps a worn tire blows out on the road. Perhaps the tire is fine but some unforeseen issue on the road causes it to blow out. Or perhaps an IED destroys the entire vehicle on the way. Any number of factors can cause delay (i.e., waiting for a particular card) or prevent something from happening altogether.
Most strategy gamers understand one cannot control every detail of a situation, so in the effort to simulate such realistic factors chaos must somehow be introduced. Whether you don't have the right cards at the right time or if the dice screw you, both methods seem to simulate this chaos in a realistic way.
Which mechanism is better? It may come down to simple preference. The argument that one or the other method isn't "realistic" enough may not be true. If you can make a case as to why one method may be better than another please share it here.
Card gamers should be more open to trying miniatures or RPGs, and RPG players and miniatures players should be more open to trying card games. Encouraging and supporting the tabletop hobby helps us all.
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