Sony's concerned Call of Duty will be worse on PlayStation if Microsoft buys Activision

engadget.com:

Sony has laid out more concerns about Microsoft's planned takeover of Activision Blizzard in its latest response to the UK's Competition and Markets Authority (CMA). Sony has opposed the deal from the start. Now, it's suggesting that Microsoft could (perhaps unintentionally) kneecap the performance and quality of Call of Duty on PlayStation, which might result in fans switching to Xbox. 

"Microsoft might release a PlayStation version of Call of Duty where bugs and errors emerge only on the game’s final level or after later updates," the letter (PDF) reads. "Even if such degradations could be swiftly detected, any remedy would likely come too late, by which time the gaming community would have lost confidence in PlayStation as a go-to venue to play Call of Duty. Indeed, as Modern Warfare II attests, Call of Duty is most often purchased in just the first few weeks of release. If it became known that the game’s performance on PlayStation was worse than on Xbox, Call of Duty gamers could decide to switch to Xbox, for fear of playing their favourite game at a second-class or less competitive venue."

Sony claims there wouldn't be a viable way for it or the CMA to assess how "Microsoft chooses to allocate its resources and the quality/quantity of engineers it devotes to the PlayStation version of Call of Duty to ensure that SIE would be treated fairly and equally." Degrading the quality of Call of Duty on PlayStation, intentionally or not, perhaps wouldn't be the wisest course of action, as The Verge points out. A buggy Call of Duty release on PlayStation would probably lead to a bigger backlash against Microsoft and Activision than Sony.

In any case, Microsoft noted in its latest response to the CMA (PDF) that it has offered to