Well, still not a substantially long run, but honestly I have no idea what the issue is.  Nothing odd on the pool side, and others run S5+'s on Eligius without issues (which means the work difficulty isn't a factor).  So, very strange.  I really have no explanation.

I did try dropping the full coinbase transaction on the node your miner was connected to for a bit to see if maybe the large coinbase was causing a slow down (used to be a problem on some old ASIC hardware that caused issues with Eligius and p2pool), but doesn't appear to have made a difference.  With the coinbase transaction dropped to a 1tx coinbase you were literally mining work that would be the same as any other pool (besides p2pool).  So, I'm at a complete loss for what the issue would be.  I still have a feeling there is some misreporting happening somewhere.

Honestly, if you're *actually* getting more hash rate for some reason on another pool and being paid more based on that, by all means mine there.  No hard feelings here.  Makes no sense to me why there would be a difference, but hey, do what you have to do.  I really just have a feeling there is something weird at play with your hardware one way or another, but without actually tinkering with it I really don't know what the issue could be.

If you want to mess around with it anymore, tomorrow some time I can setup a test node just for you (you'll still get work credit and all) that has a higher default work difficulty.  That's really the only variable I can see different between the pools at this point, even though the normal difficulty settings work fine for everyone else.

I would also be curious to how you stats look on other pools besides antpool.

Also, I do appreciate the opportunity to help troubleshoot.