Today turned into a day for pondering complexity, abstraction and memory management and watching Pirates of The Caribbean on DVD...
I experimented with a version of the buffer allocator that allowed a user defined memory allocation policy. It worked, but it was, I think, unnecessarily complex. If the buffer allocator itself lay behind an interface then that's enough flexibility. Additional abstraction, with an abstract allocation policy in addition to an abstract allocator seemed a tad too abstract... At some point you have to actually make the decision and write the code that does the work.
An interesting day's thinking; the film was good too.