Scaled objects as tooltips

In 2.0 beta, I'm using a self-generated UIElement as a tooltip, which works just great.  However, if I try to scale the element with a ScaleTransform before assigning it as the tooltip, when the tooltip shows up, the tooltip area is still the original size of the UIElement even theough the UIElement HAS been scaled.  So either I end up with a bunch of extra tooltip canvas (if I scaled the element smaller) or not enough canvas (if I scaled it bigger).

 Is this a bug in the tooltip service, or am I doing something wrong?  I guess I could roll my own tooltip here, but I'd rather use the tooltip service if possible.

 Jamie
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