That's true of some Owlswing though he had been around Catholicism all his married life and I would think Cherie is fairly mainstream.
My idea of a fanatical convert is one who embraces all the "frills" of Catholicism, eg shrines, relics, Opus Dei, penance. I am a convert too, a very long time ago, but now lapsed though I still retain an affection for the fairly liberal, post-Vat ll Church that I joined. However I came across others who wanted to be more Catholic than established Catholics:) like the types of convert described above (& found them disconcerting and rather embarrassing to be honest).
I wouldn't have put Tony Blair in that category but I suppose we don't know much about his personal faith, it is his private business after all, so you may be right.
(Nice to see you still here btw, hope you stay because you see things from different angles to many of us; no flattery intended, just how I view your posts.)