I wrote a lengthy
article for UpswingPoker about this very subject.
Tl;dr version is this: when stacks are supershallow (if we call the open, SPR= 1 or so), we can flat quite a few hands because the shorter you are the more equity you get to realize. BUT showing every flop blindly like in 2006 is completely moronic. There are hands you can call with a 4BB stack and still fold on 30% of flops. No one halfway competent uses stop and go in the very sense of the word anymore (flat BB, shove every flop). But flat BB shallow, shove lots of flops is a very viable strategy and a lot better than just shoving or folding your whole range.