Having field sense is of course something that every player strives for. After getting the basic skills it is the next target of improving players - both on offense and defense being able to anticipate where the disc should go is a useful skill to have. I always considered it something that could not be taught but must be gained from experience. But in the last few years I've seen too many egregious examples where players play mindlessly, overlooking the most simple chances to help their team. Examples:
1) The other team has a turnover. I immediately take off long. My defender is slow to follow so a second player switches to me, while my defender continues to chase me from downfield. As a result there are 2 defenders guarding me, leaving someone else uncovered. The uncovered man runs to his position in the stack.
2) My defender decides not to follow me as I continually cut short and long, but instead hangs back to poach against the long throw. As a result I am totally uncovered short, so I move in to handle. The thrower however can barely see me and doesn't have a good pass because the second handler (with his defender) is making a bunch of cuts close to the disc.
3) A handler gets the disc and has no mark. He then sits happily for 15 or 20 seconds, responding to calls that he throw the disc with "There is no stall count".
4) My team is playing a spread offense, and the mark plays a force.
There are other examples, but these suffice to show that many people play by mindlessly following guidelines that, while generally useful, are not always the best way to play. While I would hope it is not needed, here is what I think should have happened in the above situations:
1) the unmarked player immediately cuts to the disc and helps the handlers by offering a free upfield throw.
2) The handler cuts out, taking his defender with him and leaving me and the thrower with a 2 on 1 situation.
3) The unmarked handler dumps the disc off and immediately makes another cut. While throwing without a mark is a little easier, having an unguarded cutter is a much greater benefit to the offense.
4) A force is very useful in full field, 1 on 1 coverage that is needed against a stack. When the offense is using the whole width of the field for lots of short cuts a force does nothing but give a free throw to half the field.
A problem with teaching this is it is all very ad hoc. I don't think many people would disagree with the general examples given above, but how often do they occur exactly as stated without some other offsetting circumstance? It is quite possible that some other unstated factor on the field would offer a better outcome than the one I posit in my examples.
The main skill that needs to be developed is a sense of where all the people are on the field, and to see in your mind a path through them the disc can follow.
When I make a cut for the disc at the very least I know where the disc is, where I am in relation, and have a first and usually a second choice for where the disc will go if the handler throws to me. That is, from seeing my teammates locations, their motions, and their defenders, I anticipate where the useful cuts will be. When the throw comes to me I don't need to look but immediately pivot prepared to throw to the first location. If the throw is not available (the cutter did not go there, the defender is playing him well, or someone moved into the lane) I pivot to the second alternative prepared to throw there. If that throw too is not there I need to reset and look over the field.
This quick motion is effective against all defenses. A cup zone does not have that second or two to recover as the popper turns to find his next pass. The disc has moved not 5 meters but 20, and the cup is broken. Against a man it is as effective as a give and go. Defenders react to what they see and a couple quick passes are like a combination in boxing, they overwhelm the defender's ability to anticipate and react.
Sometimes the best cut is one that is not made. If a receiver catches a pass up the sideline 20 meters from the endzone the natural look is into the front corner of the endzone, so most people would immediately want to cut there. But, heads up: there may already be someone else headed there. Having 2 receivers can be helpful - one can make a bid early to try to trick the defenders into jumping when the disc is still above their reach, and the second can catch it. Or the second can be there in case of a tip or deflection. But if the first receiver is free from his defender (a 1 on 0) that is a stronger offensive position than a 2 on 1, which it will be if the second receiver cuts there bringing his defender. In this case a better move would be to make a half hearted fake long and cut across field, hoping to pull your defender away from the play.
Similarly, the best handler is the one who does not have a defender. If someone is poached and comes back to handle the cutting handler should move out. Usually the defender will go with him, giving a free throw to the poached player. Sometimes the defender might make the switch guarding the poached cutter. In this case the handler is unguarded upfield and should be able to get the disc.
The main message is to THINK. Imagine how the disc can move to the end zone and move to help towards that path.
Of course there is a down side. One is this is not a simple skill to develop, it takes time. Second is that there are dialects: the movement of one team may be very different than another, so the details of the flow can differ. Again, it takes time - time with the same people, time for a team to develop their own style and trust in teammates.
While I don't enjoy being a one note trumpeter, I believe teaching beginning players to play a stack exacerbates this problem. In a stack there are only 2 offensive players who matter: the thrower and the cutter. The other 5 are out of the play and can be ignored. As a result people never develop a playing field in their head. Because people in the stack are out of the play the cutter does not need to allow for anyone else's path when making his cut. In the stack's favor, it is a least common denominator that everyone knows. Playing pickup or in a hat tournament it takes a lot of experience to be able to cut without interfering with other players. Having everyone clear out so the cutter has the whole field to operate in means that people can cooperate even though their field images are different dialects.