Upload through Xert-app vs Zwift?

I use the Xert iOS app to control my workouts while watching myself ride on Zwift (with trainer being controlled by the Xert-app).
When the workout is finished I discard the ride on the Xert-app and save the ride using Zwift (to get the progress on Zwift). Zwift will then automatically upload my ride to Strava, Garmin, Xert etc.

Is there a difference between Xert receiving the workout from Zwift/Strava vs receiving in through the Xert-app? Is Xert doing anything fancy when it knows exactly what workout I did vs the same workout uploaded as a ride through Zwift?

Yesterday I did my hardest workout yet, a 4½ star workout (Hardness Test - Level 12 - Alternate).
I could not finish the workout at 100%, I had to go down to 98% during the last two 2 minute sections.
The finished workout is now rated as a 5 start workout and the post workout graph looks a lot harder than the pre workout graph. What went wrong? Did Xert overestimate my fitness/form, or is this the result of how the workout/ride was uploaded?

Hi @formfett ,

Good question - are you using the same power source (Power Meter or Smart Trainer) in both Xert and Zwift? If not, that could be the reason why the ‘same’ activity has a different rating. Hard to know without knowing that or seeing the data for myself! HTH