I don't believe any behavior or procedure can produce 100% accurate results. Moreover, whenever I hear someone claim 100% accuracy or rightness, I assume they're trying to bilk me out of my money.
Coincidentally CD Project just the lost the lawsuit over the DRM removal and publishing rights to xbox version. Frankly this looks just like a desperate shake down for cash as they shouldn't have anything more than IP tracking. Unless of course the game gathers personal information which would be in itself illegal.