Yes, but it'll get recorded as 60fps (the FS-100 doesn't know how to remove duplicate frames from any variable-speed footage yet). You'd have to use the FCP frame rate converter utility, or Raylight, to strip out the duplicate frames.
And you'd have to put the camera in 720p mode, not pN mode.
I've shot w/ the frame rate hack, 2fps, 350 degree shutter, but using the FS-100's intervalometer set to a variety of rates, without a problem I haven't tried the 2fps hack to the FS' normal recording mode, but I guess you'd have to use the rate converter as Barry mentioned(?)