Replying to Unwanted movement in look pivots - normal?

I'm starting to think about my setup for the upcoming season, stuff i might need to buy/replace/fix etc. I got a new pair of skis half way through last season and mounted some second hand 2015/16 look pivots I got off craigslist. I loved the skis so much I didn't really think about the bindings - I did notice that I had absolutely zero unwanted releases on those skis for the rest of the season, which was sick.

the other thing I remember about the bindings, however, is that when rolling the skis edge to edge (lengthways ?), my boots would rock over a fair bit before actually making the ski roll, making the skis feel very slow edge to edge. I tested it at home by clipping in my boot, standing on the ski to keep it flat to the floor, and pushing the boot over sideways. this would move the top of the boot almost an inch before making the ski want to tip over.
I hope that explains it well enough, might do a little diagram if needed. it was as if the toe and heelpiece of my boots were not tall enough for the binding. these being the non WTR version, I know there wasn't an issue there. my mate also got some 2017 pivot WTRs in the same season and complained about the exact same problem (and showed me) before I got mine. it annoyed him enough to decide he hates the bindings - I however didn't really mind as the tradeoff for the utter lack of pre-releases was amazing.

I did a bit of googling and searching here and couldn't really find anything - I feel like I'm using ambiguous words though because its a fairly hard problem to describe


thanks for your help!