When will a judge order that damages be determined by a jury rather than by a physician?

We considered the course followed by Osier J. in Law et al. v. Woolford et al. (1976), 2 C.P.C. 197, and O'Brien J. in Placido v. Shore et al. (unreported — July 23, 1982 [summarized 15 A.C.W.S. (2d) 537]) of leaving the issues of damages for trial by jury while directing that liability be tried by judge alone. However it is our opinion that the medical evidence respecting damages in this case will be so inextricably interwoven with that respecting liability that it is not practicable to have the issue of damages separated from that of liability.