But if it helps others too, that's a bonus. 
First I had to understand how tpms worked, and on our cars. There's 2 parts to a tpms system--the car and the sensors. This is where the trouble starts. Every car has to 'learn' the sensor IDs stored in the sensors for there to be communication. This is already taken care of at the factory for the wheels mounted on the car, but what about a second set of wheels? That's trouble because our cars can only store a single set of wheels' sensor IDs at a time.
There's two solutions to this. One, is that you have to know how to make the car 'relearn' sensors. Most documentation (including tirerack) say that you can't do this yourself, but I have strong reasons to believe they're wrong. I've attached a pdf of the best written relearn instructions I've found. It's also in the factory service manual. If you can make your car relearn sensors, you can use aftermarket or factory sensors in a second set of wheels, and then just program the car yourself. But there's one catch--you need a tpms triggering tool. All tpms sensors can be triggered at a certain frequency at close range. You do this so the sensor will 'trigger' during the relearn on the car so the car will get the sensor ID stored into the car.
The second solution is to use sensors that can clone existing sensor IDs. This way, the car doesn't even know the tires have been changed. The Dorman 974-515 is a complete kit for this including the sensors and a tool for under $300 on amazonsupply.com, but it doesn't include a triggering tool that can read the existing sensor IDs. If you already have the existing sensor IDs, this solution is the easiest.
Sensors receive at 125mhz and transmit at either 315Mhz or 433Mhz (ours are 315). The 125Mhz is used to trigger and wake up the sensors, while the other two frequencies are used to transmit data back to the car. Apparently, there's a lot of proprietary protocols involved with all of this, hence why each manufacturer had their own sensor until late. Each manufacturer kept their own protocol 'secret' so no one else would know what it is. Good idea until the company who manufactures your sensors to starts making their own sensors that work with your car. Then these sensor manufacturers got smart and started putting multiple protocols into a single sensor, hence the VDO Redi-Sensor. The problem with all this proprietary protocol mess is that all it did was make things more cumbersome and expensive for the consumer. And it still is a royal mess. The amount of misinformation on the tpms systems and process for our cars is unbelivable.
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Looks like it will be after Wednesday.