"Escher presents the world in a model called Choiceless Computation (...) Understanding the difference between Turing Machines and Choiceless Computation, while

"Escher presents the world in a model called Choiceless Computation (...) Understanding the difference between Turing Machines and Choiceless Computation, while not entirely necessary, sheds much light on the profound difference between Escher and other languages. (...) Why you should be excited: It may seem that Escher is not more than a new semantic to do an old job. But something nearly magical happens when transition to using the Escher semantic—various compiler intelligence improvements that used to be NP-hard become simple and tractable." Just there is no misunderstanding: any polynomially-bound choiceless computation (CPT+C) can be carried out by a polynomial time Turing machine, so choiceless computation does not buy you any extra power strictly speaking (CPT+C \subseteq P); and might even be less powerful than P [1]. That is not so say there might be low-hanging prefix-free benefits in average case applications due to better parallelism or easier use of heuristics, which seems to be what the author is pointing at. So be excited, but not unreasonably so. [1] http://research.nii.ac.jp/%7Erossman/yg70.pdf http://research.nii.ac.jp/%7Erossman/yg70.pdf