So most of my reference data is https://forums.tesla.com/forum/forums/temps-precondition-regen-data-graphs
and Bjorn's videos. I will work to get reference data that will show the specific scenario as written below(FACT paragraph). I am also working to attempt to get data showing heating power vs speed but that is not an easy or quick test.
Ok so here is an explanation of "preconditioning"/"battery preconditioning"/"On route battery warm up".
So all the above terms I am going to simplify as they all mean the action of putting non-motive power to the motor to create heat which then is transferred to the battery through the coolant system. Now the different scenarios as to when this function is activated create differences in how much non-motive power can be applied to the motor(s), and/or what goal temperature the system applies for the battery.
Battery Preconditioning(BC) general description: The Model 3 has the ability to put a non-motive power waveform to the motors in order to generate heat in the Stator(motor). The maximum amount of power applied to each motor is approx 3.5kW. The heat generated is then passed via conduction to the coolant flowing through the motor. This hot coolant then flows to the Superbottle(coolant reservoir). The hot coolant also flows from the superbottle to the battery, and then back to the superbottle.
Lets go through a few scenarios where BC is automatically engaged:
Routing to a supercharger:
When you route to a supercharger and the battery is less than approximately 30°C, BC will turn on and you will get a note on screen that says it is preconditioning. This BC is intended to warm up the battery in order to allow for maximum Supercharging speeds since charging a cold Li-ION battery can damage the battery. When routed to a Supercharger, BC will come on automatically whenever the car feels like it. I haven't found a good correlation on time or distance or variations thereof in reference to battery temperature. I have seen it come on automatically while being over 50 miles away from the supercharger. Now, just because the car "says" it is BC, doesn't mean that it is actually applying the whole 3.5kW(RWD), or 7kW(AWD) to the motor to generate heat. The heating power is greatly reduced when the motor(s) are being used for motion/regen. In a RWD vehicle, the BC power is greatly reduced when going over 40mph. In an AWD vehicle, the BC power to the rear motor is the same as on a RWD vehicle, but the front motor can still get the full 3.5kW as long as it is not being used to move the car. In general cruising on dry roads, the front motor in an AWD vehicle is barely used up to ~90mph.
Preheating Cabin using phone APP:
When the car/battery is cold and you engage climate control from within the Tesla app on your phone, whether you set a temperature, or hit defrost and it goes to max temp, BC will also be engaged(depending on battery temperature of course). The reason for this BC is presumably to help gain some regeneration capability at the beginning of your drive. It would also of course help supercharging speeds if you have to hit a supercharger at the beginning of your drive. I don't know what the target battery temperature for this is yet. On a RWD vehicle, it will apply the 3.5kW non-motive power to the motor to generate heat just like the first scenario above. I would presume that it would apply the 3.5kW to the front motor as well in an AWD vehicle.
So general questions relating to this have been, what is the fastest way to get rid of the regen dots. My general answer to that is, get BC turned on. Heating the cabin in and of itself is going to do practically nothing(this would be getting into the car and turning on climate control and just sitting there.) Turning climate control on via the app should do it, sitting in the car an routing to a supercharger should do it, getting in and setting climate controls and then turning on climate keeping and getting out will do it as well. Now the time to heat the battery up has not been determined yet but that is also going to depend on how cold the battery is in the first place.
FACT 1: In an RWD vehicle, during preconditioning at a standstill, the stator temperature can get from ~24C to over 55C in 10 minutes at ~0C outside temperature. https://imgur.com/a/p2rLlKS
At this point if you start driving at highway speeds, with preconditioning still activated you will see the Stator temp and battery inlet temperatures go DOWN. This indicates that even though the car is still showing a preconditioning condition, it is not actually working.
FACT 2: When you go to a supercharger and your battery is still cold, the car will continue to use BC in order to heat the battery. This is shown by the CANbus messages showing power going to the motor, the stator heating up, and an increased coolant flow rate through the powertrain and battery.
FACT 3: When setting Keep Climate ON in cold weather, after leaving the vehicle, the car will set the battery target temperature to 30C and battery heating will commence as needed.
So I just captured some data on 1/13/2020 in my LR RWD vehicle. Graph is here https://imgur.com/a/cWlOQv2
The graph starts as I am leaving my driveway and ends approximately 5 minutes after I leave the supercharger. I did not stay long at the supercharger, and the 2 little spikes while I was there were me switching stalls in order to ensure the power input was stable no matter what stall I was in. I engaged BC near the beginning as I was going 60 miles per hour. The whole point of this exercise is to show that as you speed up, the preconditioning goes away. This graph shows that as speed increases, the stator temperature levels off and/or goes down. I will also note, that if I had done this trip without BC on, my stator temperature would probably not have gone above ~25°C. Questions welcome. Ohh and yes the radiator was bypassed 100% the entire time.