When you use these types of dischargers and you want to put some stock in the numbers, make sure you do it the same way and record your numbers.
Ie: Run 5min in same format with same type of motor. Come off the track and put this on the battery. If you use a different format (stock vs. mod) just record it. Eventually you will get enough data!
Now you will know what your battery will putout voltage wise, resistance and how much run time you had left.
Where this comes in handy (since the numbers could be questionable) is when you compare your packs.
After several cycles (as long as you record your findings) you can see the packs getting better and better.
I have found the packs do take more charge, are stronger out of the corners and some of my practice packs have even become race packs again.
I have also found when the resistance numbers become erradic, thay my joints had become questionable. Resolder and all is good and the pack is back on track.
The other way is to do it full charged to bechmark your packs. I also take my packs (undischarged after a run) to work with me the next day and use the discharger all day long.
Hope this helps.