Is there a penalty for switching to PPS and back to Prop too often?  I've had several instances where I would switch to PPS and then get the next 5 blocks at 50% of normal Prop payout.  The 6th block would be 20% normal and then full PPS.  The reverse was true when I went back to Prop, (20% then 5 @ 50% before full Prop payout).

I noticed back about 10 pages someone was commenting that they were being paid out less than expected, they were getting the same percentages, but they didn't specify any other conditions.