On a more serious note. How much power does a CRDT actually produce? How much was the car actually putting out as stock? Plenty of cars put out more power than the manufacturer claims.
So unless an insurance assesssor is going to run your car multiple times on a rolling road back to back with and without the box how are you really going to know the true figures? Plus the CRDTs are adjustable. Who says you’re running it on full fat mode?
19.99% extra power for insurance purposes then don’t have an accident doing illegal speeds where they might actually delve into it a bit closer.
Its not necessarily about risk based on you having the extra power... its to do with that those people who normally make this modification have a broader risk profile that is higher than those who choose not to.
Much like adding some vinyl flames up the side or swapping your OEM wheels for some third party ones.
All of these things suggest that you may be the sort of person with an enhanced risk - and that's all its about, profiling of the data to make a financial risk model. Its not scientific really, its not fair in a lot of ways but its how they roll.