Interesting observations thanks.
I cant recreate this because I have a larger SNRm and any capping will only further increase it.. but it could explain why I see less errors on the Zyxel?
Ronski's may be another good case to compare. It shows that on his line there is less aggressive bitswap. Interesting that he also sees the evening peaks though when it ramps up similar to when on the HG612. - See the screen caps in his thread
here.
Looking at his graph today, I notice that as predicted he will now see more ES due to the fact that interleaving depth was reduced on the 26th but it still seems to be performing within acceptable parameters. Whilst he is getting more E/S its not bothering the DLM .. plus he's getting a sync increase of 2.5Mbps.
On the whole I'd say Ronski's line seems to be doing quite nicely with the VMG8324 and seems pretty stable.