Re:" so look at the lesson it can draw from this screwup."
"If you say to an accountant"? We have all too many examples in industry where the bean counters drive strategy - look where that's got a lot of firms. The correct question that MS should ask themselves (not their double entry bookkeeping onanists) is in fact "is there not a possible cost associated with this that we have not taken into account"? If they think long and hard the answer will come to them. "Yes there fucking is. We are on the ground floor of trying to create a big slice of what is going to be a mega-global business far larger than it is today (because it is currently in its infancy and still very dependent upon customer trust) and fuck-ups like this could cost us billions if not trilliions in lost future customers". Then they should spend whatever it takes and (if necessary) engage in cost cutting elsewhere in the business - they could start by firing all accountants at senior manager level or above.