Routing newb question:

I've got a fiber optic cable I'm running that has a minimum bend radius.  I was hoping to use Routing to define how to get it from point A to B without exceeding that minimum. 

It appears that the minimum bend radius in the routing box is only for pure elbows.  When I make a tubing route from a 3D sketch it doesn't use that radius for the corners.

I've  just swept along a 3D sketch in the past with a spline pinned to a planar sketch to limit radii but I was hoping routing might be simpler to ensure the minimum radius.  Was I wrong in this respect?