I do not think its a problem of Bkool. Chain eats some power ~5w, tire ~10-15w. Bushido measure power correct, for tire. But the problem that all races have different PM-sources and nobody knows which one. That is why some groups have +20w, another -20w. Simple zPower has option to adjust output power, but nothing for bushido
Thebreal problem is that Zwift doesn’t car WHERE power comes from. If you had a power meter in your shoe, another in your pedal, another in your crank, another in your hub, and another on a trainer, and assuming they are all reading 100% accurate, the power will reduce from first to last in the same order.
At some point Zwift will probably normalize all power to match trainer power by subtracting a percentage of other types of sensors… But in order to do this they will need to compile a database of all available power types and then get people to tell them in the app what type they are using.
Its sort of like the zpower debate. Zwift has put tremendous effort into supporting the vast majority of trainers and now you see almost no flyers… But soon you are going to start seeing people complain that, “that guy is cheating by using a Vector! It’s not fair!”