what was VMS/OpenVMS written in?

I don't necessarily agree that assembler is required "to get full optimization of performance" today because of the work that's been done over the past three decades or so in compiler design. Modern compilers are written to take advantage of every trick available on the target platform such as load hoisting, redundant load/store elimination, loop unrolling, conditional execution and the like, over varying code scopes that aren't apparent across a project of a non-trivial size. Perhaps a really really good assembly language programmer could produce code a tiny bit faster than a reasonably well-written compiler could, but at what cost in development time? I certainly agree that "more hardware - MORE!" is not the solution, which I think is an important part of the argument you make. BTW, improvements in compiler technology was an argument I used as a test manager with ${a large software company} when I told coders in code reviews it wasn't acceptable to write indecipherable code because "it would be more efficient." Today I use the intermediate variables I need to make the code's functionality clear (and maintainable), because I'm confident they'll be optimized away by the compiler. That's not just opinion - I've tested it. :-) -- Ian