Well, price engine is very simple one for some hotels then, where in example for Le Meridien BKK Z3R total paid rate always equals to 3 nights pre-paid rate.

5400x2=10800 with tax or something equals to 34xx (don't remember exactly at the moment) plus tax x 3.

Which at that moment didn't impress me at all, since that was clearly a message - "If you like promo rates, please use it, but you will pay exactly the same, as without the promo"