Related to this thread https://developer.apple.com/forums/thread/737819
I can confirm (again) that GPS performance on the watch Ultra (and likely all watches on watchOS 10) had been severely degraded.
Here is a swim that I did with both an Apple Watch Series 4 on watchOS 9 (green track) and a watch Ultra on watch OS 10.1 (blue track).
While the Series 4 provides relatively accurate data, the Watch Ultra provides very poor data with criss crossing paths and ridiculous data points.
Apple did respond to my feedback with the usual request for sysdiagnose but this has not progressed. FB13192409
