Evidence of mental disorder required for s2 detention

“Today it is difficult to come to a definitive conclusion whether X is suffering from a mental health condition” on its own does sound quite ambivalent but, as you said at one point, we don’t have all the facts (and I have to admit that I haven’t followed every twist and turn of the discussion). You asked on another topic for a legal opinion, and it would definitely make sense to speak in person to a solicitor who could obtain all the relevant information – I’ll reply to that topic with some ideas about who to contact.