Hi, Rajan,
Doug - Lloyd Chambers is a meticulous reviewer and his reviews have been quite useful to me in my choice of lenses. You are perhaps right, he must not mean that literally.
I think what we can say is that the TS-E 17mm is an (essentially) rectilinear lens with an (angular) field of view about half that of a fisheye lens.
As I understand it, its (diagonal) field of view on a full-frame 35-mm format camera is 93°. More-or-less by definition, a fisheye lens has a field of view of nominally 180°.
As I understand it, the field of view of the TS-E 17mm, with respect to its entire image circle, is 121°. That results from the size of its image circle, which is of itself certainly important, as it is one key to the lens' shift capability.
But at any given shift setting, assuming a full-frame 35-mm format body, the field of view is only 93°.
Best regards,
Doug