“20. So far as relevant to this appeal, the effect of a Tomlin order is that a claim is compromised on scheduled terms. Further proceedings in the claim are stayed except for the purposes of carrying those terms into effect. The effect of a stay is not equivalent to a discontinuance: the stay may be removed if “proper grounds” or “good cause” are shown (Cooper v Williams[1963] 2QB 567 , 580, 582).”