It is not always possible to mimic / reproduce the same journey / weather conditions and driving style that your historical data has used to predict your estimated range advertised by the GOM,
If you have a high mileage recorded on the accumulative trip, that has been built up over the same repetitive journey and in excellent EV weather conditions, and view this prediction as actual achievable range, then out of the blue, you take on an unknown long trip in different weather conditions, with cabin heater etc, you maybe wondering why you range is diminishing faster than you thought.
An over inflated optimistic range can only be 100% believe IF you are able to mimic the trips 100% of the time.
If I intended to make an unknown journey that could stretch the range to the max, then I want a more accurate base line to work from.
Resetting both trips before I commence the journey will display the default predicted range and not an inflated range built up over say 1,000 miles of town driving etc.
None of this even worth considering when the trip is well inside of the range envelope of current SOC of course.
If you have a LR version this is less stressful because you have more range available to start with.
We had the previous Gen 1 version and it was easy to build up the predicted range on the GOM over a few weeks of careful driving in ideal weather conditions.
After charging the car, it would report having an inflated predictable range.
If I was then to take on a unknown trip, believing that this prediction was correct, I would come up short !.
Resetting the trips, would return a more accurate predicted range that could be 20 miles lower than the original figure.
A 20 miles difference is a lot on car that was 2 years old and covered 20,000 miles, that certainly had some small amount of battery degradation.
SOH was around 95% ( ish ) on our car, others owners have reported similar values on the forum, for cars of that age and mileage covered.
This figures can be witnessed by reading the BMS update thread on the forum.
Warning

- You will need a GOOD few hours spare to read through it all !.