Re consideration: I would have thought that this is a statement of a general point, but within the boundaries of a specific special case (ie letters of credit). Doc credit has always happily bumbled along ignoring considerations requirements (as it rightly should, in my opinion). As such it's probably nothing worth writing home about. (as Andrew Tettenborn has just beat me to pointing out).

However,  it seems to me that there is no rational reason for this distinction, other than a form of backward reasoning so as to explain why Pillans v Mierop was wrong. The usual reason given for the lack of a consideration requirement in documentary credit is that doc credit is sui generis. Yet why do we think this, especially in light of the fact that (a) doc credit is very old, at least as old as any consideration requirement (and if one goes far back enough with consideration, one begins to see its inherent problems), so it should not really be consider some sort of novel upstart, and (b) consideration gets in the way (at least, in very many of the cases) - why should something that gets in the way be considered the norm? The only rational reason for the sui generis explanation is that attempting to reconcile it with our (conservative, and to my mind, mistaken) understanding of consideration necessitates the claim that consideration is the rational structure and doc credit the exception. If we flip that, and see consideration for what it really is - a messy nonsense (arguably just a means by which judges can deem certain agreements to be enforceable or not, according to their particular feeling of that appropriateness of the transaction and whether it should be enforceable), then we could begin to see the problem for what it is: we have spent far too much effort on trying to explain and justify the inexplicable and the unjustifiable (ie consideration). 

But I always feel that I'm pointing out a giant blaspheming elephant when I talk to proper contract lawyers about this...