Estes Express Lines in conjunction with Bell and Strick trailers have made an innovative new pup trailer design.
*not my photo.
The "pot belly" (my term, not theirs) part of the pup has movable floor sections that can support a forklift when loading the front of the trailer (over the fifth wheel) after which the sections can be loaded and then lowered into the belly, allowing for more vertical space for additional loading area.
It is an interesting concept, and I could see it becoming common throughout the LTL sector.
Of course, it's just more things to break, but that's with any new bit of equipment.
I can certainly see the movable sections collapsing under a forklift, requiring a visit from the local wrecker company.
Or stuff getting caught under the lifts and either damaging the lifts or punching a hole in the floor.
And the obvious for any low-profile vehicle: bottoming out. Such a short trailer will probably help avoid that for the most part, but still, it'll probably happen.