can someone PLEASE explain the PriorOutcome feature generator?

[Jim foo.bar]

I've asked a couple of times before but I got no answer! Jorn replied to 
me at some point but his response was very brief and confused me even more!

I'm begging you!!! I'm writing a paper for BMC bioinformatics and I 
cannot explain this feature properly! I'm struggling to find information 
on the web...


PLEASE, PLEASE, PLEASE, devote 5 minutes to explain what this feature 
does and how it works. An example would be awesome...

thanks in advance...

Jim