When looking at Per User Completion Timelines and Per User Completion Dates, the graphs seem to account for all tasks assigned to a user.
It seems the correct thing to display is "all tasks assigned to a user in a current milestone".
For instance, I know I'm working on XYZ, and it's set to "Unassigned" for the Milestone, but it makes it look like I'm going to finish Milestone two weeks late even though I only have 3 hours left in the project.
Some of the other graphs (Burndown, etc) don't appear to have this problem.
(OT -- It would be awesome if I could open up a bug on FogBugz using FogBugz and be able to search previous bugs reported against it. Kind of crazy that I can't. But then, proprietary software, right?)
FogBugz Version 7.2.17 (DB 741, Build 1634)