TF loops in urdf with branches

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Hi I have noticed loops created in transform chain when I ask for a transform between the root to a child in a tree with multiple branches.

Eg: head    -> imu_link
            -> laser_link
            -> camera_link      -> camera_optical_frame

When I perform a tf_monitor from head to camera_optical_frame, I get a chain like this => head->laser_link->head->camera_link->camera_optical_frame.

The loop head->laser_link->head is unity when the links are stationary. It becomes a serious issue when the links are moving as this loop need not be unity. I understand TF is trying to match both time and frame and this might be a side effect of it as It is not taking a snapshot of the joint states before transforming but getting joint states as it computes. Is there any way to disable this. In a multi frame humanoid this is a serious cause of the TF to be slow. Currently in cases where I need TF lookup fast I use KDL and extract my chain of interest and perform the FK.

Please give me your opinions and suggestion on it. Could it be possible that the way I am setting up the robot might be wrong?

Thanking you, Benzun