Does Zwift "Estimate" cadence?

I’ve been using a new bike that does not have power or a cadence/speed sensor on it.  I use a Cycleops Powerbeam Pro.   When I download the Zwift file and manually upload it into Garmin, I’m seeing cadence.  However, no cadence is shown on Zwift when I’m using it.   Are you calculating this in the background?  Or is there some freak thing happening with my DI2 and cycleops Im unaware of?   

The cadence is “estimated” by measuring the “pulses” in your pedaling, i.e. the less smooth your pedaling style is, the more accurate the cadence figure comes out. This is done by the trainer and transmitted to Zwift.

Thanks for bringing this up! I’ve created a known issue article for this, and we’ll be working to fix it in a future update.