There was a time I was actually going to build a miniaturised version of the two prism thing and stick it on rails in front of my camera!

Good luck with the shader experiment, I hope you can pull it off, I look forward to seeing what you come up with.  I've been experimenting myself, I've managed to get Bryce to do Anamorphic rendering even without the ability to scale the camera along an axis.  That at least means there's more than one way to do this even though until yesterday, I thought there were none!

But yup, in Bryce the trick is to use Camera Space and you can do Anamorphic renders!  I'm especially pleased Bryce can do it, she never fails to be able to pull off a rendering or material effect, there always seems to be a way to do everything in Bryce when it comes to that stuff.

Bryce version attached, again not applied very hard, Anamorphic on the left, standard on the right.  Anamorphic bokeh looks so much better.  I hate standard bokeh in comparison, especially from renderers because standard bokeh almost always looks like that toy camera effect.