The 'swivel-lift' concept is an idea I've seen replicated faithfully in various 3D representations of the bridge by people on the internet over the years, but I've gotta say I've never understood it. Where did it come from? Was it ever part of the original Probert/Zimmerman set design?
The first time I saw it was in Shane Johnson's Mr. Scott's Guide to the Enterprise
. With the only two doors on the classic movie Enterprise bridge both leading to turbolifts, how else does one access the docking port immediately behind?