I am no engineer (well I am an engineer but not for concrete) but we did a shotcrete pool. The concrete was poured in October and I let it sit all winter (without plaster). The pool did not crack or move. No problem with the dirt around the pool as it had a good solid winter to settle. The pool was finished in the spring and we are just getting to start swimming. Shotcrete seemed to be the best option when I researched pools. I have at minimum of 12 inches of concrete in the walls of the pool and much more around the base (all reinforced with rebar). From an engineering perspective, I was quite impressed with the structure - arhhhh arhhh arh (I like BIG). It took a long time to build and costs a lot of money but I am really happy with what I got. This thing should last forever.

I always beleive that you get what you pay for (except if you go to a pool store )