RotateElement:Element rotates temporarily and then reverts to original position

[dirk.neethling]

I rotate an ELement (FamilyInstance) using the following code:

Line lineAsAxis = Line.CreateBound(new XYZ(0, 0, 0), new XYZ(0, 1, 0));

double rot = ConvertToRadians(90);

ElementTransformUtils.RotateElement(doc, elem.Id, lineAsAxis, rot);

THe ELement rotates successfully, I can see it in an instant during debugging, but then reverts to its original orientation upon completion of the Execute Command. Code runs in a transaction. What could be the reason for this?

[dirk.neethling]

I found out I am working with adaptive Elements, thus the question is irrelevant.