That's true but why try a speculative sac when you can gain an easy edge without trying
4. Nxd4 or O-O

If the sac worked everyone would play it but they dont
The problem is that the Blackburn-Shilling is not played very often. So if people face an move they dont know the probally try to make priciple moves (which is fine) or think, or get anxious of the oponent.
So Bxf7 is an near to nothing played answer to an only few played gambit. So it is not well known for its merrits.
And in my experience most of the people tend to play the same opening even if they lost beacause the oponent did find the reight moves on an dobius or bad line.
Yes I mean that's definitely a good bluff and very triable and even playable, but be careful if this is refuted because you should always take into consideration your opponent's best defense.
yep they don't