I know some people have used shift lenses to produce Panoramas
But I can't quite understand why one would want to do so.
It is far easier to increase focus with a program like Tufuse within PTAssembler, than it is to
than to try do the same with a swing shift lens. PTGui also has this capability.
It is far easier to just point the lens slightly upwards, than use a shift lens, to get more of the top of a scene in the frame.
All the panorama software automatically correct the resulting distortions. Or if more coverage is needed, make two or more rows.
PTGui can handle images taken with a shift lens. Compensation for the off-centre optical axis iis achieved using the vertical and horizontal shift parameters d & e in the optimization (measured in pixels).