Oh, no problem, I understand what you're saying quite well :)   One of the things I do for living is in construction industry, mapmaking and land surveying ;)    
I was trying to pace myself so I don't make things too complicate for those whom may not be as familiar with the industry... but I'm delighted with your depth of understanding. It will just make things more fun and easier to communicate :))

Hi, my namez: "NO, Bad Kitteh, NO!"  Whaz yurs?
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