Huw wrote, in part:
>...of course all the more experienced divers on
>the boat have been running through a whole load of 'if only' scenarios
>since then.  Possibly we should have explicitly advised him not to
>dive, but ...

Nonsense!  Neither you, nor any other diver on that boat owed him had any
such obligation.  He is a certified diver.  He, and he alone, must
determine if he should do a given dive.  The whole point of being certified
is to learn to dive safely and responsible.  Not to be a permanent burden
on those with whom you dive.  In hindsight his decision was unwise, and he
but others at risk.  He should be apologizing, and no one else.  It sounds
like his rescue was textbook.  Everyone who responded should feel pride,
not guilt.

It is very nice to hear he has recovered.

Have a great time in Scotland!

Dive safe,

/Don