this was really just an idea to make icsdroid even more attractive and because I didn’t know about etag support in icsdroid. I just checked and most of my feeds do, I just wrote to teamup.com support to ask if they could add it
And it came to mind for the other use-case I described (respecting the cache-timeout header if the server sends one) because per-collection sync would be a prerequisite.
Honestly, icsdroid works great for me, this is just to foster it’s position as the best tool available 8-)