I run an Equal-i-zer and if you pop the bar free anywhere in its range of motion, then you should check to see if you mounted the brackets too far from the coupler. Personally, I am from the camp where need to have that kind of extreme pinch should not exist when negotiating into a site. You can (and should IMO) work the trailer in-place with more, gradual moves. I say this because think about how you are loading the axles (and worse, the China bombs) when you push the tongue that way. However, to each their own.
With any WD setup, such angles will put considerable unbalanced stress in the A-frame and it's especially true with the Equal-i-zer because of the design. I have seen a few damage their L-bracket and/or L-pins under two scenarios: 1) turns just as you are asking about because note the stress the spring bar "inside" that angle exerts on everything, and 2) backing a trailer up a decent incline while the TV remains fairly level. The design can only handle so much rotation in that direction. So, where the Equal-i-zer design is concerned, I personally do feel there are times when you should pull the bars for backing.
I'm going on 15 years running an Equal-i-zer, and I can pretty much judge unconsciously when I need to pop the bars and when I don't. I've run a lot of style of WDH over the years, and I'll never run anything other than an Equal-i-zer when ball towing again!