I don't have a primer, per se, for asymmetrical tilts/swings, but I'll "talk" you through it here. It's really pretty simple.
Of course, you need to decide where you want to place your plane of sharp focus and then choose reference points to focus on first.
Let's consider tilts:
Choose a near and a far reference point. Ideally, one of your reference points falls on the tilt axis (let's say one does for now - the other reference point can be anywhere, but the farther the points are from each other on the ground glass, the better). Some cameras have two tilt axes usually, one high and one low, marked on the ground glass. You can tilt around either. I think some cameras only have one tilt axis.
At any rate, choose the axis you want to tilt around (easy choice if your camera only has one), but don't tilt yet. Simply bring your reference point into sharp focus using the main focusing knob. Let's say we focused on the "far," using the bottom axis on the ground glass.
Once this point is in sharp focus, tilt the back around the tilt axis (in this case, the top of the back will move backward) until your second reference point is in focus. Voilà! You're done. The far point will still be in focus, since that part of the ground glass hasn't moved. (Note: if you choose to swing around the top axis, i.e., the "near" point, then the back will tilt in at the bottom to achieve the same result.)
What if your reference point doesn't fall on your tilt axis? Well, the easiest thing is to find one that does. Next easiest is to use your rise/fall to position the reference point on the axis, apply the tilt and then re-frame using the rise/fall. If that's impossible, then find one as close to the axis as possible. You'll have to do a couple iterations to get both your reference points in focus though (like using axis tilts with reference points on either side).
Now, on to swings:
Replace "near" and "far" in the above with "right" and "left."
There's a pdf document from Ebony that describes asymmetrical movements in more detail here:
http://www.mr-alvandi.com/downloads/...el-cameras.pdf
Hope that helps,
Doremus
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