To start, let's break down man-defense to the absolute basics: the marker is forcing the disc to one side of the field. The defender is taking away the cutter's space to that same side: voila, defense! Where the core concept starts to become complicated is when we start dealing with dump defense; because unlike down-field D, the dump defender has to cover both down-field and backfield space to shut his man down.
I'm not going to get too much into dump defense; I could write a ton on that subject alone (hey, another blog entry!), but the idea I'm trying to get forth here is that getting open on a dump is easy because there is far too much space for a defender to reasonably cover. However, so many handlers eliminate this advantage by simply setting up their initial spacing incorrectly. So, a large portion of what I outline below will be where to setup and why.
Before we actually begin talking about setup and execution of dump cuts, I have to reiterate what I've said in so many entries before: take what the defense is giving you! Don't feel like any kind of default positioning or preset cut supersedes how the defender is actually playing you. If someone is playing five yards off, don't cut into them, take the free pass.
Also, think about what you're trying to gain from a reset of the disc: you want an advantage on the field, just like with any other pass. It's not just about a new stall count, it's about putting yourself into a position with the disc that benefits your offense more than the previous position.
Ok, all of that aside, let's talk about some actual handler cuts. I'm going to default to a vert stack two-handler set for my examples, as it's what I've run most consistently for the teams I'm coached/captained in the past several years. That being said, there isn't really any big difference between what I'm going to outline here and a three-back setup, except with three you are slightly more limited in your horizontal space.
Part 1: The Disc is in the Middle of the Field
Let's start with the disc in or near the middle of the field. Given the opportunity to set up ideally, you want to be on the FORCE side of the disc as a dump (three handler sets will obviously have handlers flanking either side of a centered disc). One reason to set up force-side, is if the handler-defender poaches off into the lane, you would rather have them poaching the force-side than the break side lane. But Katfish, why would I want a poach cutting off my force-side cuts? That's my first look!
There are two reason's you'd rather have a force-side poach than a break-side poach. First of all, with a break-side poach, to actually get the disc to the poached handler either your dump has to move, or you have to break the mark, both of which take time. Additionally, you don't gain a whole lot, and the poach has effectively disrupted your offensive flow.
Second, with a force-side poach you can immediately hit that poach without interference from your mark and take off up the line for an easy give-and-go, securing yourself power-position (catching the disc with your body moving in the direction of your next throw).
Note: In all of my diagrams the lines are defenders, the circle X is the disc, the X is the dump, and arrows indicate potential disc or player movement.
In the right diagram, the defense is sagging into the break lane. To take advantage of this poach, the thrower has to turn away from the down-field and either the dump has to run horizontally across the field (blue arrow) to get the disc behind the thrower, or the thrower has to break the mark slightly (red arrow) to get the disc out to the dump in space. Even if the disc does get to the poached dump in this scenario, very little has been gained. The continuation break is easily stopped and you don't gain power position. Your best bet here is to ignore the poach. However, doing that eliminates a portion of your break throwing lane, which isn't good for any offense, horizontal or vertical.
In a three handler-set, simply prioritize looking to the force-side to beat the poach rather than the break side to keep in line with what I've talked about so far.
Bad teams run into problems with a force-side poach (and thus argue that you should set up break-side for your dumps) when they stare down-field into that poach or hit the poached dump without making the continuation cut up the line. In these cases you're either throwing into a poaching defender, or moving closer to the sideline without gaining yards or power-position, aka it's bad. Don't be the bad team, throw and go!
Learn the Angles
The second reason you want to set up your dumps on the force-side, is that it makes for the simplest and quickest reset. The key principle here is understanding the dump's positioning relative to the disc-marker's positioning and how that affects throwing angles.
When setting up for your thrower as a dump, you want the line between your shoulders to stay parallel to the the disc-marker's shoulders. Assuming you are on the force-side of the disc, this positioning keeps an equivalent throwing angle to either down-field or backfield space for the thrower to make for an easy reset. Obviously, the mark will not be completely stationary, but you still want to maintain the parallel setup as best you can as they shift.
As you can see in the above diagrams, the specific force is not important. What's important is that the dump stays parallel to the disc-marker, so that there is always equal space to either side to make an easy throw. In all three examples you can see that the thrower can throw to equivalent space on either side of the dump, without interference from their marker, as long as the parallel positioning is maintained.
In the above diagrams, the dump has failed to maintain proper position relative to the disc-marker, and has made the throwing angles nonequivalent. A smart dump-defender in this case will shade their defense toward the side where the marker has more throwing space, which opens up the potential for the dump to be shut down, or at the very least, makes for a more difficult throw.
While it's reasonable to expect a thrower to be able to make slight break throws, we're trying to simplify the reset process as much as possible. Just like with our force-side poach, if the thrower can just turn and hit the dump (because the disc-marker is a non-factor on a force-side throw), it makes the reset a no-hesitation play; fakes don't need to be made, the dump doesn't have to do anything but wait for the space throw to the appropriate side. This has the added benefit of avoiding miscommunication turnovers where the dump effectively out jukes their own thrower.
Ok, we've established proper positioning and why we're doing it. Let's now talk about this "easy space throw." When you've set your dump up correctly on the force-side, the defense will play you one of three ways (assuming they're not poaching):
1) The defender has conceded the down-field space by opening their left hip. Here, the thrower leads the dump out into that down-field space, a few yards are gained and the new thrower will have slight power-position.
2) The defender has conceded the backfield space by opening their right hip. Here, the thrower leads the dump out into the backfield space. This is now a great opportunity for a continuation break throw, and the disc is kept near the middle of the field.
3) The defender is keeping their hips parallel to the dump's hips or "faceguarding" the dump. Here, the thrower has the option to lead the dump into either down-field or backfield space, as they will have the reaction advantage since their defender has no vision of the disc. (To gain vision of the disc the defender HAS to turn one hip or the other away from the dump.)
To make this kind of reset work, the dump needs to stay close to the disc. The farther away from the disc you are, you the longer the throw will be in the air and the longer the dump-defender will have to find it and block it. The initial separation advantage won't be huge, whether it's from the defense's initial setup (the first two examples above), or from the delay in knowing the disc is in the air (the third example). But with a decent throw, even a less athletic handler should have plenty of time for an easy reset, as long as they aren't off 10+ yards away from the disc, allowing the faster defender time to react and overtake them on the throw.
Some throwers aren't completely comfortable making a space throw to a stationary receiver, but with the proper positioning and a little practice, this type of reset is easy and automatic. Resets in general shouldn't take long to develop and should always be an easy throw because they are gaining you little relative to a down-field completion. With this setup and assuming your throwers are comfortable with an easy, space throw, resets from the middle of the field rarely will result in a turnover and will usually gain your team more than just a new stall count.
In part two, I'll discuss resetting the disc from the sideline.
Disclaimer: Everything I write is my own opinion about Ultimate tactics. Many teams run different setups than what's outlined in my blog with great success. If you disagree with anything written, please post in the comments as I always love to learn about new or different concepts.