A Wired blog post has an interesting take on timing of the docs' retirement, suggesting a possible connection to vesting of a deferred equity payout from EA's acquisition of BioWare, as follows:

Electronic Arts acquired BioWare in October 2007. EA noted at the time that it would pay an additional $155 million in equity to “certain employees” of the company, subject to “time-based… vesting criteria.” Zeschuk and Muzyka’s concurrent departures come almost exactly five years after the acquisition.

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