Otherwise he seems to have described asynchronous message-passing style, except with convoluted programming language concepts. But Microsoft already has a compiler that statically analyzes message passing in large programs; look up the Singularity operating system. [TL;DR: Message-passing microkernel; everything runs in supervisor mode; safety is checked statically at compile-time.]
Unordered collections is just too lax to be useful: for example, multiplication of 100 matrices can be nicely parallelized because multiplication is associative, but not commutative. So you'd probably end up defining write-once locations ("boxes") that contain (ordered) vectors of elements and use that for communication. So, back to I-structures.