In the US, any wires that are contained within the box, ie, jumpers or pigtails, do not contribute to the box fill. In your case with 3 sets of 14/2 wire and two devices in a plastic box, the total would be 22ci.

Eric, please don't take this the wrong way, I'm not trying to be a wiseacre. Randomly connecting stuff to various pairs of wires isn't going to solve your problem. The basic problem here is that you don't have quite enough basic electrical background yet. Two errands. First, go to the hardware store and/or cheap tools store and get yourself some basic test gear. You need a DMM (digital multimeter) that can measure resistance (continuity). Also get a rubber light bulb socket with wire pigtails, and a 7 watt night light bulb that fits it. (The links are for illustration only, and are not meant to be endorsements.) You'll see how to use these after the next step..... Which is, go to your library and check out one or two books on basic electrical wiring for the homeowner. (Ask the librarian for help if necessary.) Read them all the way through. When you read about how switch loops work, I bet the light bulb will go on. (Sorry, bad pun.) With your new tools and quick education, you should be able to figure out which wire goes to what. If not, hop on back, and we'll see if we can help. Electrical wiring isn't all that complicated, it just has certain conventions that you need to learn. Good luck! Let us know how it goes.

"As for the code, I can see both sides of this discussion. To my recollection, though, no device *ever* specified looping in its instructions. Despite that, it was a fairly common method 30-40 years ago. What's changed?" Just because guys have been "doing it that way for 30-40 years" does not make the practice right or even code compliant. It isn't. They don't call them "terminals" for no reason, you know. They are called "terminals" because that is where conductors are meant to terminate and end....not "pass through". ---------- For the record, I am an AHJ and an electrical inspector. For existing work that had no other practical alternative but to continue to use a looped conductor, I'd permit it. For use in new work, I'd reject it everytime. Because if you plan properly, there is never, ever any reason to use that wiring method. Ever. But I'm sure there will be some older (and younger) ones who would disagree.

Here's a chart that may be of some use. Also, this page has a downloadable spreadsheet (requires Excel or something similar enough to run Excel spreadsheets).