The distribute loss action will work as green-up or red-up
So I took another look at this tonight.
I backed Under 2.5 goals, waited a minute until the priced had moved enough for me to green up, then I turned on the trigger to see it distributing the loss i.e. greening up. Nothing happened, this is the log:
20:46:36 None of the selections qualifies for a distribute loss between selections.
20:46:36 Condition is: TRUE. valid for 2 selections: Over 2.5 Goals, Under 2.5 Goals.
20:46:36 Checking condition and Selection's Trigger Expression ABS(UnderPL-OverPL) is greater than 0.15.
So, green up doesn't always work, neither does distribute loss. Therefore it seems that I have to do something non trivial to get MFP to actually green up for me.