An update on the Assassin's Creed Unity Live Updates blog reports the results of an investigation into the "no face" bug some users are reporting in Assassin's Creed Unity, saying this is only occurring for users of a couple of specific video cards, but that this no longer strikes those who have applied the game's day one patch. There is also another update to let us know they are currently testing some optimizations to improve performance, and they claim they are addressing problems in the live game that somehow did not show up during testing:

We can tell you that we have detected a distinct discrepancy between what we observed in the pre-launch versus post-launch environment. In spite of our testing, it looks like the instruction queue is becoming overloaded and impacting performance. We have several fixes we are exploring right now and will continue to update you with our progress of what is working and how quickly we can implement these fixes in the game in the weeks ahead.

Meanwhile, we are looking at the following revisions that should improve framerate stability for all players:

• Streamlining some technical aspects of navigation: We’ve fixed a number of edge cases with our detection system to smooth certain behaviors during parkour. We’ve fixed a few objects which were improperly tagged to smooth navigation.
• Improving task scheduling: We’ve tuned the way the computing tasks are prioritized and parallelized by the processor cores to improve framerate in certain edge cases.
• Tweaking performance for Reach High Points: We’ve optimized the reach high points, during the camera swooping sequence to improve framerate a little bit.

Though crowd size was something we looked at extensively pre-launch, it is something we continue to keep a close eye on. We have just finished a new round of tests on crowd size but have found it is not linked to this problem and does not improve frame rate, so we will be leaving crowds as they are.

We’re working very hard to see these changes rolled out in Patch 3, but as we’re still testing our fixes we need to be conservative with any estimates as far as ETA is concerned. We hope to have further updates on this topic before the end of the week.