Fuel Tankering Sections

[Will C 5]

I see there are some interesting section types in PFPX:

 

TankerGain
TankerLoss
TankerNotAvial
TankerSavingsGain
TankerSavingsLoss

 

It's clear to me how to enter, say, 1000 lbs of fuel in the fuel ladder for tankering, but I don't see how to use those section headers in PFPX. Presumably each would get (by way of example):

 

<&TankerGain_Begin> and <&TankerGain_End

 

And then there would be relevant content within the section. It looks like possibly a way to show the cost savings, by tankering differing amounts of fuel.  I'm sure it's too much to ask for a tutorial on what to place within the section delimiters, but is there an OFP template that uses them that I could have a look at? I was looking through the OFP templates that come with PFPX and I couldn't see any that put these sections to use. 

 

Thanks.