You could but the results would be unpredictable because SetMatrix() updates the entity position, rotation, scale, etc.
Here is a list of members:
http://leadwerks.com...ntities#Members
The following are the documented members of the Entity class. Generally, members should be treated as read-only. For example, setting the entity position by changing the position vector values will fail to perform necessary updates the SetPosition() command would call, and the results may be unpredictable.