Its amazing that the car club pays so little attenion to their published fixes.
Overwhelming the fuel system to overcome your problem may be the cheapest way but it would get us professionals a $10k fine.
The resistance of the temperature sensor is non-linear. To get an example of the way what you are doing affects the system here are the values. They are semi approximate. When cold the sensor has about 2000 ohms resistance. The addition of 470 ohms is say a 25% increase to the richest running conditions. When the car is at 180 degrees the sensor is around 200 ohms. Now your fix is modifying the sensor value by over 200%.
During early EFI, Porsche and VW added a 200ohm resistor to their very similar temp sensor. The whole point (during an era where mixtures were 10 times higher) was to alter hot restart conditions. The point of this fix was that they could make a significant change in hot conditions without making much difference in cold conditions. This is also what this fix will do. If you are effecting your problem cold imagine what you are doing hot.
You are masking the problem. If your car was a year or two newer It would tell you about it with a check engine light.
Bosch Master, ASE Master, L1
33 years MB technician