Slow Frames & ProMotion

[jjnino]

Hello! I had a question / concern regarding how the slow frames working with ProMotion displays like the ones in the iPhone 13. According to:
https://developer.apple.com/documentation/quartzcore/optimizing_promotion_refresh_rates_for_iphone_13_pro_and_ipad_pro
the device can variably update its refresh rate from 10Hz - 120Hz which means sometimes screen renders are happening at 100ms intervals. It would seem that the slow renders functionality would produce false positives? It also seems like you can get the expected refresh timing by leveraging the targetTimestamp. It kind of explains that in the link above and also here:

The code listing below shows how to calculate the actual frame rate by dividing 1 by your display link's timestamp subtracted from its targetTimestamp.

// Calculate the actual frame rate.
let actualFramesPerSecond = 1 / (displaylink.targetTimestamp - displaylink.timestamp)

in https://developer.apple.com/documentation/quartzcore/cadisplaylink

Thanks!