MPH switching performed poorly yesterday too. I think we may be seeing the effect of all our asics.
yesterday
2018-07-12 (UTC) 0.00354236 (btc)
vs 3 previous days
2018-07-11 (UTC) 0.00439799 (btc)
2018-07-10 (UTC) 0.00454665
2018-07-09 (UTC) 0.00440286
I had similar results on MPH as well, with yesterday being a down day. What did you get on 7/8/2018? That day was even worse than yesterday for me so I suspect down days are normal.