There isn't a principle in the Constitution that you can't make look foolish by conjuring up some ridiculously extreme fact situation, however unlikely. This idea, which I'd like to claim as my own, is so old, however, that the Romans had a name for it and they got the idea from the Greeks who stole it from some earlier civilization, no doubt: Reductio ad absurdum.
"But counsel if we rule your way, doesn' t the sky fall in short order?"
That's the slippery slope version, to which the reply must be along the lines of "But Your Honor, seeing as how you happen to be in charge of the slipperiness of the slope, we can count on the slope being quite sticky, just as your question demonstrates this court's commitment to a sticky, not a slippery slope."
Or one could say that we must protect the fringe to protect the core, otherwise we have a slippery slope in the other direction that eats up core values.
Try not to step in the bs that passes for legal and political discourse. It's slippery.