I did an FTP testing using my 945 on my trainer using my new power meter and I copied the TrainerRoad protocol (20min ramp) which calculates FTP as 75% of your best 1min effort. This worked out to be 234w (best 1min was 312w). Garmin awarded me a new calculated FTP of 224w for the ride. Obviously there is some difference in how Garmin calculates FTP compared to TrainerRoad's method, anyone familiar with those differences?. Here is the link to Garmin Support about FTP but I don't see anything about their calculation (which is probably proprietary).