It has been a known issue for years that bones continually shrink 0.001% or so as movements/rotations are made ( http://forums.adobe.com/thread/37356 ). I experienced this problem to the extreme in CS4 with the shrinking compounding up to 20% over the course of 1000 frames. Recently I purchased CS5.5 and was disappointed to see this problem still exists. I love the faster speed of the bone engine but this problem is a huge thorn in the side of serious IK bones users.
Is there a setting or something I'm missing? I have unchecked the "auto transform" option in Preferences -> Drawing but it hasn't seemed to change anything other than forcing the bone to connect to the transform point. I have also tried resetting the scale in the Transform panel after each movement but it's both tedius and inneffective. I long for the option to lock the scale of bones in an armature but it doesn't seem to exist. Is there anything I can do to remedy or better cope with this bug?