What is the current interpretation of Lord Mansfield’s rule in the context of title disputes?

In more modern times, Lord Mansfield’s rule has been refined. It has been narrowed to where the plaintiff relies on illegality to establish his or her case. The modern rule was stated by Lord Browne-Wilkinson in Tinsley v. Milligan, [1993] W.L.R. 126 (H.L.) at 153: In my judgment the time has come to decide clearly that the rule is the same whether a plaintiff founds himself on a legal or equitable title: he is entitled to recover if he is not forced to plead or rely on the illegality, even if it emerges that the title on which he relied was acquired in the course of carrying through an illegal transaction. and further: In my judgment the court is only entitled and bound to dismiss a claim on the basis that it is founded on an illegality in those cases where the illegality is of a kind which would have provided a good defence if raised by the defendant. In a case where the plaintiff is not seeking to enforce an unlawful contract but founds his case on collateral rights acquired under the contract (such as a right of property) the court is neither bound nor entitled to reject the claim unless the illegality of necessity forms part of the plaintiff’s case.