I understand what you are saying about "physical" vs "logical", but our company (a defense contractor) must use a certain tool and that tool must have SLOC, so we are stuck trying to figure out the "physical" and put in factors that may try to make the comparisons accurate. The tool requires things like "Do you have experts working on the project or novices" and "Have you used the same hardware in the past" and "Are your development tools highly automated"...
I am going to try and get our Cost Engineer involved in this discussion if it gets interesting, she has lots more insight than I do about our tool.
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