I get what you are saying Swatski, the rear crossmember would be exposed as you come into the lift (with the bow of course)
Again, if your bunks are up out of the water, you should not have been approaching it. The front, on the other hand is technically impossible. The boat cannot slide across the bunks out of the water and get that far into the lift to reach the front cross member. There is no amount of power loading that can get a 4500lb+ boat up on that thing with the bunks out of the water.
Here is one other thing that supports a "proper setup" The front of my bunks are much higher than the rear of my bunks. So that being said, if the bunks are under water, the rear cross member is well below the surface, let alone the draft of the hull. And by the time the bow is near the front, it has already made contact with the bunks. So the slope of the bunks is the third variable. It's all in proper setup of the bunks as mentioned.
One last note, on my Floe lift, my bunks extend past the rear of the lift quite a ways. To the point that even if up, they could be set to keep the hull from touching even if up. I would never do that, as having the rear bunks separated adds stability to the boat on the lift once in the air.
I hope that clarifies this for you.
I attached a visual of my lift prior to canopy install last year. And this was at a dangerously low level, before I put all four posts up higher. I had about 2" of clearance from the cross members.
Note, the rear posts and bunks are lower, than the rear. The front are higher, but also slightly narrower. When down, there is no way for my hull to hit the cross member, as it will always hit the bunk first. It will always auto center as well, since I have width differences. And if I am more forward or back from time to time, it will not change that, as the rise of the bow, will clear the cross member.