What's going on with FindName!

I've noticed some really odd behaviour with FindName and Beta2.  I have a stackpanel to which I add canvas each with a name.  When I execute a stackpanel.FindName(canvas name) command it will return a null even though I can directly verify that the stackpanel has a child canvas with that name in the debugger.

Now it seems that FindName will only return the canvas when executed on the actual control itself; this is a custom control derived from Control.  So executing a this.FindName(canvas name) actually returns the canvas.  What the heck is going on here?  Beta1 was working fine and moreover this was not included in the breaking changes doc!
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