Well xbox one games are known to be overtracked because of npd

Yeah but we are only talking about physical sales here.

Everyone knows software numbers are very inaccurate because it is simply much harder to track software sales. And hence there is no point in even proposing a wholesale adjustment of the entire software library of a platform. The only time adjustments in software are feasible is when the shipment or sell through number for a specific game is announced by the publisher or developer.

Otherwise 10% under or over for the total software library is doing OK.

At present VGC has 89 games listed with sales >1. And at least several dozen countries in which those games are sold. Also even though there may be certain stand out games that appear to have sold better than can be believed, it doesn't mean the usual big sellers are totally accurate either. Collectively the CoD and Fifa games could be 1 million over tracked. But because they have sold several million no one would ever notice 1 million here or there for these titles. So if ioi slams down the apparently obvious overtracks by more than is justified because there is a hidden 1 million overtrack among the big selling titles then he will not have improved the accuracy of the individual game estimates at all, even though he will have appeased the sensibilities of some people by making the total game sales across all games more closely match official PR on total software sales.

You might be but I'm not 

If you psychicly know what is over tracked why wait for ioi?