Equalizer spring arms - what to look for

Background: New TM 3124KS, Equalizer WDH, lousy walk-through by the dealer, new to towing

My understanding: In the process of unhitching, you raise the tongue jack "until tension is relieved from the hitch bars." I am not able to see any visible change in the spring bars when I raise the jack higher. What exactly am I looking for? The arms appear to be straight at all times (no bowing). I figure I'm either looking for the wrong thing, or my hitch isn't adjusted quite right.

First time I did this, I may have even raised it too high, looking for "tension to be relieved" and then had to lower it before I could free the bars by trial and error. Tips appreciated.

Thanks for your help.