Think of the soft top as having 4 positions. From most coverage to least, there's closed, Sunrider, fully open and all together removed from the rig. I think the position you refer to is Sunrider position. If so, a picture's worth a 1000 words. Decide for yourself if what you see meets your criterion. In 2 and 4 door respectfully appears Sunrider position below. It can most certainly accommodate highway speeds and comes with tie down straps to keep it from closing.
I've never used the tie down straps although I hear they're useful in a cross breeze, perhaps when driving at local road speeds. On the highway, I can't normally imagine any wind force more powerful that the one from the rig's speed keeping it open.