After struggling with a migration from our custom image management solution using IC, to proper Image Manager, I have done some findings which I would like to share. It would have saved me much time and frustration if the following was documented in IM User Guide or elsewhere.
1. Piez report of "Optimized Realtime" doesn't work if you modify the 'server' response header.
Apparently there is some validation of certain response headers for Piez to work.
2. Image Manager use different user-agent headers when doing Realtime versus Offline fetch of pristine images
Realtime: Mozilla/5.0 (X11; U; Linux x86_64; en-US) AkamaiImageServer VelocitudeMP/1.0
Offline: Mozilla/5.0 (X11; U; Linux x86_64; en-US) AkamaiImageUploader VelocitudeMP/1.0;IM/1.0
(Someone claimed also Mozilla/5.0 (X11; U; Linux x86_64; en-US) AkamaiImageServer VelocitudeMP/1.0;IM/1.0 is in use, but I have not seen it)
Hope this could be helpful//