I have seen this style done correctly only once and that is in the 7th edition View Camera Technique by Leslie Stroebel.
On page 143 in chapter six (6.15) sub titled, Trick Perspective, is this:-
Alignment of the image inside the frame with the background creates the illusion of a transparent body, an application of the Gestalt organizational law of continuation.
The first picture your link goes to, is the best.
Interesting concept, something I have been wishing to do for some time.