"I would NEVER hire an embedded programer to work on it that only knew C and was not proficient in the underlying assembly language"

I can't imagine why not. Do you really mean 'proficient' rather than 'able to understand'? I certainly fall into the latter category - as I said above I've never written any 8051 assembler (actually, thinking about it I have added a few lines to startup.a51 from time to time) although I do occasionally need to read assembler when checking the compiler's output or analysing 'legacy' code. I can do this but pretty slowly!

I realise that a good knowledge of the processor's architecture is essential when writing embedded 'C' but this is quite different from being proficient in the native assembler.