An interesting aspect to this that seems to be overlooked is that the conventional intelligence was probably intentionally fudged in order to garner funds and s

An interesting aspect to this that seems to be overlooked is that the conventional intelligence was probably intentionally fudged in order to garner funds and support and raise anxiety and fear as a means for motivation. You can't overestimate the production of tanks by that much when you are observing the production facilities. You would either have to have been tricked, i.e., knowing that it is being observed the same tanks were "shipped" multiple times or you, for some reason thought there were more factories which you didn't have eyes on. I'm not sure how to judge whether it would have been in the Nazi interest to provide an impression of high productivity or hide the true nature of the numbers. Another interesting aspect to this is that it provides the background for why the US military operates with what would otherwise be seen as abject retardation. There is a strategic value in being aimless, illogical, and confused in your operations for various reasons. One reason is that if you have "random" serial numbers your enemy can't do these kind of calculations.