You guys are really good saying that I can't be right because PART of the evidence does not support me and yet:
I have 300+ furnaces
I have 300+ scanners
I have under 20 trashcans, sewer lids and whatever other stuff that drops from rancor. Explain that with your "random" theory.
As I was farming carbantis for GK with an aproximate 10% drop rate, I saw precrafted carbanti in shipments 3 times during the period of 4 days. The 200 cuffs I farmed right after had a 40% drop rate. You say standard deviation, I say for games with this revenue model you should assume the worst, and be pleasantly surprised if you are ever PROVED wrong.
By the way, I havn't seen a single carbanti in shipments since i finished my slow grind
/edit
Let me make this perfectly clear: I am NOT saying there are dynamic drop rates, i am only saying that it's WRONG to ASSUME that there are NOT dynamic drop rates. If the drop rate was constant, why would they keep it a secret?
Anyway, good work on your numbers, most of the time it's exactly my experience as well.... most of the time.