The decision of the House of Lords in R (Purdy) v DPP [2009] UKHL 45 (the assisted suicide case) clearly has nothing to do with housing law but, as a general statement of law, para. 34 is very interesting.
… it is obvious that the interests of human rights law would not be well served if the House were to regard itself as bound by a previous decision as to the meaning or effect of a Convention right which was shown to inconsistent with a subsequent decision in Strasbourg. Otherwise the House would be at risk of endorsing decisions which are incompatible with convention rights (per Lord Hope).
Might we see this paragraph relied upon in the (inevitable) future challenges to Kay?
Well spotted! Your nose for relevance outside the housing field is commendable. Personally, I find it almost impossible to keep up with housing case law, let alone assisted suicide, which is why NL and Legal Action are so useful.